Brand Love, Attitude, and Environmental Cause Knowledge: Sustainable Blue Jeans Consumer Behavior

Abstract

A blue jeans brand committed to the environmental cause could position itself as unique and socially responsible and attract environmentally driven consumers. This research study examines the relationship between brand love and consumers’ environmental cause knowledge and their willingness to recommend and pay a premium for sustainable blue jeans. To this end, this cross-sectional study comprises a snowball convenience sample of 978 Portuguese respondents, whose data were collected from December 2022 to January 2023. Positive associations between self-expression, brand love, loyalty, environmental cause knowledge, positive word-of-mouth, and willingness to pay a premium for sustainable blue jeans stand out. There are differences in the willingness to pay a premium among generations, education levels, and consumers who are aware of sustainable line extensions and those who are not. The results may be helpful for brands, suggesting their communication should focus on creating increased proximity to consumers by enhancing their values and seeking to link their brands to intrinsic benefits and environmental stakes. This is the first study to incorporate knowledge of the environmental cause into a model linking brand love, brand loyalty, positive word-of-mouth, and willingness to pay a premium for sustainable blue jeans.

1. Introduction

The environmental impacts of the fashion industry are widespread and significant, as the industry is a heavy water consumer (approximately 79 trillion liters per year), producing 8 to 10 percent of the global CO₂ emissions and large amounts of textile waste, most of which ends up in landfills or is incinerated, including unsold products [1].

In addition to being globally popular, blue jeans are associated with somewhat problematic sustainability and social responsibility issues [2]. The traditional jeans production process uses excessive amounts of water, chemicals, and energy, thereby generating a negative impact regarding the carbon footprint [3]. In order to remove excess dyes and achieve the desired color, blue jeans are washed at least twice before being sold; globally, approximately 3% of the water used in agriculture goes into cotton production [4] to produce more than 2 billion units per year [5]. Another factor contributing to environmental degradation comprises the chemical products used throughout the production process (from insecticides and pesticides), even in cotton production, which accounts for 2.4% of the world’s arable land use; other chemicals are used to dye and paint the jeans, which have a significant environmental impact if not properly handled and disposed of in the environment [6].

Over the past decade, growing awareness of environmental issues and increased consumption have encouraged apparel brands to adopt practices that cause less environmental damage and incorporate social sustainability practices into their operations and value chain management strategies [7]. Many brands have started adopting sustainability strategies and policies to integrate such concepts and improve their image [8]. Some have started to introduce and create sustainable extensions [9]; the examples include H&M, Zara, Pull & Bear, and C&A, who have launched sustainable lines with items made from recycled and organic materials. The blue jeans market has also adapted to the new sustainability paradigm, developing substitutes for toxic chemicals, introducing resource-saving technologies, and generally applying sustainability practices and new developments in jeans supply chains, from raw material selection to the reuse of used clothing [10,11].

In recent years, there has been an increase in the research on consumers’ awareness and adoption of sustainable clothing behaviors [12]. An increasing number of consumers advocate purchasing sustainable fashion products to meet their psychological needs, reflecting their attitudes toward equality and sustainability. Consumers are increasingly aware of sustainability [13] and are demanding that companies take action. However, they often need to be made aware of their responsibilities and the impact of their consumption [14].

Consumers who tend to buy products from fast fashion brands prefer low prices, and according to Mandarić et al. [15], buying clothes from sustainable brands is generally not dominant in consumers’ behavior, although they show concerns about climate change and pollution; they also believe that their conscious consumption has a positive impact on the environment, although it does not yet influence their purchasing decisions when buying clothes—showing an attitudinal behavior gap [16]. In fact, consumers who are more concerned about environmental issues have the ability to choose between greener and more traditional products [17]; however, despite growing concern about fashion brands’ unethical practices, this concern is not always reflected in their behavior [18].

Consumers are often skeptical of marketing campaigns in which companies claim to be sustainable and admit that they may benefit economically from doing so; in fact, some companies advertise products as green or organic when only one element of the production process meets this claim [19]. Despite the still low levels of sustainable fashion purchasing, more and more consumers are questioning the impact of their clothing purchases [20]. This suggests that brands should provide transparent information about the sustainability impacts of their products; however, these products should remain relatively similar in style, quality, and price to conventional products to facilitate consumer choice and encourage sustainable purchasing [21].

One barrier to purchasing sustainable clothing is the need for more options; as companies work to provide more sustainable options, consumer perceptions of sustainable products compared to similar conventional offerings are changing dynamically and must be considered by brands [22]. According to Kim et al. [8], brand extensions are the application of an established brand name to new products in order to capitalize on the heritage of the original brand and capture new market segments. The inclination to accept offers for items in a sustainable brand extension can be facilitated if the consumer feels love for the brand and is loyal to it; brand love, the most intense relationship between a consumer and a brand, strengthens brand loyalty [23]. The main positive effects of brand love are brand loyalty, positive word-of-mouth, and willingness to pay a higher price [23,24].

Although there is evidence that a company’s sustainability can affect its image, the impact of sustainable lines on brand image has yet to be determined; Hill and Lee [25] argue that the literature lacks consumer perceptions of fashion brands’ sustainable actions, making it difficult to develop effective marketing strategies when launching these products. The motivation to focus this study on the product category of blue jeans stems from the recognition of the significant impact on the environment, given the intensive use of materials, methods, and industrial processes with high ecological impact, on the one hand, and taking into account studies that suggest the development of research based on models centered on brand love (e.g., [26]), incorporating dimensions that can help better understand the determinants of behaviors such as those mentioned above, namely in the Portuguese sustainable blue jeans clothing market.

Therefore, in order to address the aforementioned gap, this article proposes the following questions. Focusing on blue jeans brands, will consumer loyalty to sustainable blue jeans extension lines, possibly at a higher price, be facilitated and encouraged if the potential buyer loves and is loyal to the brand on the one hand and is sensitive to the environmental cause on the other? Is brand identification with the jeans’ consumer (self-expressive brand) a determinant of brand love? Do consumer love and loyalty for jeans brands induce positive word-of-mouth? Are sustainability-oriented consumers more willing to pay a premium for items from sustainable lines of jeans brands?

In this context, the next section examines the relationship between brand love and consumers’ environmental knowledge and consumer behavior, particularly in terms of the willingness to pay a premium for sustainable jeans and to positively recommend the brand to others. The next section also develops hypotheses to test in this study.

2. Theoretical Background and Hypothesis Development

Brand love is a concept that has been widely researched and discussed in recent years and is related to the holistic and hedonic proposition of the brand, which ultimately leads to purchases [27]. However, brand love creates a deeper connection between the customer and the brand [28]. The difference between someone who likes a particular brand and someone who loves the same brand lies in their personal experience, which is known as their brand experience, a concept correlated to both feelings; therefore, brand love not only represents a more intense feeling than liking but also has different theoretical concepts [28]. According to Gumparthi and Patra [29], brand love results from “passionate feelings and emotional attachments that satisfied consumers have for brands”.

Carroll and Ahuvia [27] define brand love as the degree of passionate, emotional involvement a satisfied consumer has with a particular brand; brand love includes passion for the brand, attachment to the brand, a positive evaluation of the brand, and positive emotions in response to the brand. These authors introduced the construct of brand love separately from interpersonal theories as a combination of interrelated behavioral, cognitive, and affective processes; they also emphasized the integration of self-expression to explain brand love (positive effect), as well as the effects of hedonic products on brand love (positive effect) and brand loyalty (negative effect).

Carroll and Ahuvia [27] also make a distinction between brand love and brand satisfaction. First, brand love has a much stronger affective focus. At the same time, satisfaction is a specific result of a transaction; brand love is often the result of a long-term relationship between the consumer and the brand. In contrast to satisfaction, brand love requires no expectations (the consumer knows what to expect from the brand), involves a willingness to express love, and involves the integration of the brand into the consumer’s identity—none of which are prerequisites for satisfaction. Both the brand and the consumer interact on several levels, from the most superficial to the deepest; the latter involves a high degree of passion and emotional attachment, which can be considered brand love [27,30,31]. Consumers love a fashion brand because of the passion it inspires in them; fashion brands seek to capture and attract markets of young consumers who want to express themselves through fashion, who in turn can pass on positive feedback to other consumers [32].

Carroll and Ahuvia [27] developed a ten-item scale to measure brand love, focusing on passion, involvement, positive evaluations of the brand, positive emotions in response to the brand, and declarations of love for the brand, combining these individual components into a unidimensional construct. This approach has been criticized because many researchers consider brand love to be multidimensional [33]. Despite this criticism, Carroll and Ahuvia’s [27] concept is the most widely applied in the literature. Bagozzi et al. [26] also developed a brand love scale based on qualitative studies conducted by Batra et al. [23], which identified characteristics of brand love experienced by consumers, namely related to brand love itself and its consequences (brand loyalty, positive word-of-mouth, resistance to negative information, and willingness to pay a premium).

Identification with a brand is a determinant of the brand [24,34] and may be more significant the more closely it is linked to the consumer’s self-concept [35]. To achieve their identity goals, consumers use brands to create and represent self-images and to present these images to others or to themselves [35]. Thus, the relationship between the brand and the consumer captures an essential part of the consumer’s construction of the self. Therefore, the primary dependent variable in our studies measures the extent to which consumers incorporate the brand into their self-concept. In addition to their role in the construction of the self, brands help individuals convey a particular image to others [24]. Carroll and Ahuvia [27] conclude that the consumers’ love should be greater for brands that play a significant role in shaping their identity; therefore, they define a self-expressive brand by consumers’ perceptions of the degree to which a given brand enhances their social self and reflects their inner self, thereby postulating the hypothesis that is also replicated in the present work:

Hypothesis H1:

Self-expressive brands have a positive association with brand love.

As Bagozzi et al. [26] point out, not all people have a strong love for some brands, nor are all brands likely to evoke feelings of love in consumers—known as neutral or low-love brands. However, an empirical study of neutral brands by Batra et al. [23] found that 80% of the sample expressed at least some love for a brand, which was found to be predictive of brand loyalty and positive word-of-mouth. This finding suggests that even in the case of brands with low or moderate involvement, where it is unrealistic to admit to much love for the brand, some love can still be helpful [36]; brand love is a predictor of relevant consequences—such as loyalty, positive word-of-mouth, and willingness to pay a premium for branded products—and many authors emphasize the relevant role of brand love in developing and maintaining the relationship between the consumer and the brand [34,37,38].

Brand loyalty describes the desire to maintain a long-term relationship with the brand [39]. According to Chaudhuri and Holbrook [40], loyalty is a combination of underlying behavioral, cognitive, and affective processes; for these authors, brand trust and affection are essential determinants of brand loyalty. Brand loyalty can be defined as conative loyalty [41], that is, the degree to which the consumer is committed to repurchasing the brand. Based on the assumption that the brand represents subjective value to the consumer, they view loyalty as a commitment, determination, and a desire to continue the relationship with the brand [40].

Authors such as Albert et al. [42] argue that brand love influences brand loyalty. Sarkar [43] states that the relationship with passion determines the repurchase intention and that romantic brand love shapes behavioral brand loyalty. The links between passion, commitment, and brand loyalty show a possible relationship between brand loyalty and brand love [44]. Brand loyalty can result from brand love [27,39,45].

Carroll and Ahuvia [27] define positive word-of-mouth as the degree to which consumers are willing to spread positive and complimentary messages about a brand. Satisfied consumers who also love the brand are more likely to repurchase and are more likely to spread the “good word” to others [27]. Positive word-of-mouth can be understood as an outcome of a consumer’s relationship with a brand [32] and includes making others aware of doing business with a company or store, making positive recommendations about a company to others, or praising a company’s quality orientation [46,47].

A price evaluation is a crucial influence on consumer behavior (price-related or behavioral intentions); a fair price predicts the consumer’s willingness to pay for it [48]. In the literature, the research has focused heavily on analyzing customers’ willingness to pay as a key behavioral intention (e.g., [49]). The willingness to pay a premium can be seen as the willingness to remain a brand customer in case of an increase in the company’s price level compared to other brands [48,50]. On the other hand, several studies refer to the willingness to pay more for a product as a result of the development of brand love (e.g., [51]) because the consumer sees the brand as unique and without alternatives or because they want to continue to feel the emotions that the brand gives them. Brand loyalty also influences behaviors such as positive word-of-mouth [36,52] and willingness to continue buying the brand even after a price increase [24,45,53,54], while mediating the relationship between brand love and these behaviors [24]. In light of these considerations, this study proposes the below hypotheses.

Hypothesis H2:

Brand love is positively associated with positive word-of-mouth (H2a), brand loyalty (H2b), and willingness to pay a premium (H2c).

Hypothesis H3:

Brand loyalty is positively associated with positive word-of-mouth (H3a) and willingness to pay a premium for sustainable jeans (H3b).

The results of a study by Hill and Lee [25] show the influence of knowledge about the environmental cause on the evaluation of sustainable brands (or those that offer consumers sustainable line extensions). The study concludes that consumers perceive sustainable products as a fit for fashion apparel brands based on their prior knowledge of the brand, on the one hand, and their commitment to the environmental cause, on the other.

Consumers who are more knowledgeable about sustainability issues, namely the environmental cause, tend to develop favorable attitudes toward sustainable brands [55,56] and recognize the suitability of sustainable brand extensions [25], thereby influencing the purchasing of sustainable brand items [57,58,59]. Hill and Lee [25] highlight the relationship between environmental cause knowledge and consumer behavior in terms of willingness to pay a premium for sustainable items. On the other hand, it is reasonable to assume that knowledge or ignorance of sustainable alternatives to blue jeans affects consumer behavior [60]. Therefore, the below hypothesis is proposed.

Hypothesis H4:

Knowledge of the environmental cause is positively associated with the willingness to pay a premium for sustainable jeans.

Gender is a commonly considered variable in marketing; it is reasonable that consumers are not treated as a homogeneous segment, as there are several differences in terms of gender [61]. For example, the literature states that male consumers are more likely to take risks than women [62], which indirectly shows a high level of commitment and brand loyalty in women [63,64]. However, women are more likely to make impulse purchases than men [65] and report more hedonic aspects, such as emotional arousal (for example, brand love) [66]. In this respect, the levels of brand love and loyalty tend to be generally higher among women, which will positively influence their willingness to pay more for sustainable products and to spread the good word about their preferred brands to others. Age is also a characteristic that can explain different consumer attitudes and behaviors and brand loyalty. Younger consumers are generally more open to new brands because they value innovation and are less loyal to existing brands. It is possible that newer brands will have a younger consumer profile and established brands will have older consumers; on the other hand, younger consumers have less purchasing power, which will affect their willingness to pay a premium, especially for sustainable clothing, even if they value ethical consumption. In any case, the relationships between age, the brand, and sustainable consumption are not sufficiently considered in the literature [67].

Several authors recognize that gender and education level can create differences in behaviors related to clothing consumption, namely ethical or sustainable consumption [68,69]. Chen et al. [70] report that women are more likely to be involved in ethical consumption, receive information about ethical consumption from others (more about fashion), and feel good about being an ethical consumer. A quantitative study by De Wagenaar et al. [71] of more than 500 consumers found that women owned more clothes than men in all categories of the study (total number of clothes, including unused and used); in the same study, consumers aged over 30 owned more clothes, while those under 20 and over 51 owned more unused clothes. A study by DeLong and Bang [72] concluded that baby boomer women (members of the generation over 58) seek more mature and timeless clothing, although the same is true for younger generations, as both are influenced by an environmentally conscious culture (leading to more sustainable clothing consumption). A study by O’Cass [73] concluded that women are significantly more involved in clothing fashion than men; the same is true for young consumers compared to older ones. Pauluzzo and Mason [74], on the other hand, looked at generation Y consumers or millennials (members of the consumer generation born between 1980 and 1995), who are said to be the ones who consume the most fast fashion products (still accepted as the social norm), discarding used clothing more frequently and without considering sustainable ways of doing so. However, they acknowledge that millennials are aware of the social and environmental impacts of clothing consumption and are willing to pay more for sustainable products, which is perplexing because these attitudes and intentions do not translate into actual behavior in the same way. In addition, younger consumers are more likely to value constant change and are more prone to impulse buying [75]. Higher levels of education may also positively influence sustainable purchasing behavior [76]. A study by Rahim et al. [77] found significant differences in consumer behavior for sustainable products but did not find them in age or education level.

In the literature review conducted for this study, there was an apparent lack of studies on the possible association of sociodemographic characteristics (gender, age, generational group, education level) with the behavior of consumers of sustainable clothing, especially in terms of the propensity to give positive word-of-mouth reviews and pay a premium for this type of item, providing opportunities for future research [78].

Figure 1 illustrates the conceptual model explored in this paper, highlighting the relationships between the constructs described above.

3. Methods

3.1. Procedures and Instruments

This quantitative study was based on a structured questionnaire survey with items developed by the author and items previously used in published studies, namely scales by Carroll and Ahuvia [27], Habel et al. [48], and Hill and Lee [25]. The items of these scales were translated into Portuguese. Then, the questionnaire protocol was created, which also included a section with sociodemographic items and questions about the respondents’ preferences for jeans brands and purchasing behavior.

The questionnaire was first completed by 15 students to check if it would raise any questions or require any adjustments. The final questionnaire was then sent via Google Forms to students who were asked to share it with others, creating a snowball and convenience sample. The response collection period was from 1 December 2022 to 10 February 2023. The inclusion criteria for participants in the sample consisted only of being Portuguese, 18 years of age or older, and having purchased blue jeans in the past two years. All participants were previously informed of the research objectives and were assured of the anonymity and confidentiality of their data, accessing the questionnaires only after giving their consent. The collected questionnaires were validated and processed in SPSS Statistics 28.0.1.0 and SPSS AMOS 28.0.0.

The questionnaire included sections with the following:

• Questions of a sociodemographic nature, including gender (female, male), age, and level of education (basic education, secondary or vocational education, higher education).
• Questions about jeans consumption habits: A question determining the eligibility of the answer (“Have you bought blue jeans in the last two years?”), about the respondent’s knowledge of any sustainability concerns of their preferred brand (“Do you know if your preferred jeans’ brand has sustainable processes and products?”), about the recent volume of jeans purchases (“How many blue jeans have you bought in the last two years?”), and finally on the type of store where the garments are purchased (“Where did you buy jeans last time?”; “physical store”, “online store”).
• Items used by Carroll and Ahuvia [27] to measure the variables self-expressive brand (eight items), brand love (eight items), brand loyalty (four items), and positive word-of-mouth (four items), measured by a seven-point Likert scale (1—strongly disagree to 7—strongly agree); items used by Habel et al. [48] to measure willingness to pay a premium (three items), measured by a seven-point Likert scale (1—strongly disagree to 7—strongly agree); items used by Hill and Lee [25] to measure knowledge of the environmental cause (three items), measured by a five-point Likert scale (1—strongly disagree to 5—strongly agree).

3.2. Data Analysis

Although the sample was a convenience sample, meaning it was not representative of the Portuguese population, it was of an appropriate size for the exploratory nature of the study. The minimum number of desirable responses for the sampled Portuguese population (approximately 10 million people) would be 385, with a confidence level of 95% and a confidence interval of 5%. The survey yielded a much higher number of 1055 responses. First, cases that did not meet the eligibility criteria or had incomplete responses were excluded, resulting in a final sample of 978 cases. The analysis of these data began with the characterization of the sample, namely in terms of the respondents’ sociodemographic profile and shopping habits, and of the items (30 questions) using descriptive statistics (mean, standard deviation, percentages, asymmetry, and kurtosis coefficients).

A new nominal variable, the generational group, was generated from the variable ‘age’, with four possible values [79]: generation Z (under the age of 28), generation Y or millennials (between the ages of 28 and 42), generation X (between the ages of 43 and 58), and baby boomers (over the age of 58). Since the group of respondents with a primary education represented only 4.5% of the sample, it was decided to group them with the group of respondents with a secondary or vocational education.

The normality of the data was checked for the 30 Likert questions. Next, a principal component analysis with varimax rotation was performed to validate the scales and reduce the number of (single) variables to a simple component structure. The PCA yielded a six-component structure corresponding to the variables proposed in the literature (self-expressive brand, brand love, brand loyalty, environmental cause knowledge, positive word-of-mouth, and willingness to pay a premium).

The reliability of these scales was then examined by calculating Cronbach’s alpha and assessing the convergent and discriminant validity, namely by determining the correlations between the CR and AVE constructs. A confirmatory factor analysis (CFA) was then performed in SPSS Amos, confirming that the data fit the conceptual model by analyzing the calculated values of χ²/df, CFI, SRMR, and RMSEA.

The structural equation model then allowed the evaluation of the hypotheses establishing the relationships between the constructs (H1, H2, H3, H4, and H6) and the mediation of BLY in the relationships between BLO, WOM, and WPP (H5a and H5b, respectively). Differences between categories of sociodemographic groups were analyzed for the constructs to evaluate hypotheses H7, H8, and H9, using t-tests (for gender, education level, and knowing or not knowing sustainable alternatives groups) and an ANOVA (for the generation group).

4. Results

4.1. Sample Characteristics and Consumer Habits

The sample was approximately 61% female and 39% male (

Table 1. Sample characteristics (N = 978).

Variable		Frequency	Percentage	Cum. %
Gender
Female		596	60.9	60.9
Male		382	39.1	100.0
Education level
Basic and Secondary/Vocational		460	47	47
Higher education		518	53.0	100.0
Generation
Generation Z (18–27)		589	60.2	60.2
Millennials (28–42)		198	20.2	80.5
Generation X (43–58)		160	16.4	96.8
Baby boomers (>59)		31	3.2	100.0
	M	SD	Min	Max
Age	30.1	12.5	18	77

Note. Cum. %—cumulative percent; M—mean; SD—standard deviation; Min—minimum; Max—maximum.

). The predominant age group in this study was generation Z (60.2% of respondents), followed by millennials (20.2%), generation X (16.4%), and baby boomers (3.2%). Most respondents were in or had completed higher education (53%).

Table 2. Blue jeans consumers’ habits (N = 978).

Variable	Frequency	Percentage	Cum. %
Number of blue jeans purchased in the last 2 years
1	72	7.4	7.4
2	200	20.4	27.8
3	171	17.5	45.3
More than 3	535	54.7	100.0
Where was the last purchase made?
Physical store	848	86.7	86.7
Online store	130	13.3	100.0
Do you know if your favorite jeans’ brand has sustainable processes and products?
No	559	57.2	57.2
Yes	419	42.8	100.0

Note. Cum. %—cumulative percent.

documents statistics on aspects related to jeans consumption. More than half of the respondents had bought three or more items in the last two years (54.7%), preferred physical stores (86.7%), and did not know if their preferred brand uses sustainable processes and products.

4.2. Item Descriptors and Reliability

Prior to analyzing the data, the normality of the items was examined using the indices of asymmetry (Sk) and kurtosis (Kr). Absolute values of Sk less than three and Kr less than 10 indicate a normal data distribution [80], which was the case for the 30 of the items in question (

Table 3. Item descriptors and reliability.

	Variables and Items	M	SD	Sk	Kr
Self-expressive brand—AEB; Scale from 1 to 7; Cronbach’s α = 0.947.
AEB1	This brand symbolizes the kind of person I really am inside.	2.52	1.219	0.287	−0.835
AEB2	This brand reflects my personality	2.69	1.256	0.116	−1.033
AEB3	This brand mirrors the real me.	2.50	1.217	0.309	−0.850
AEB4	This brand is an extension of my inner self.	2.42	1.218	0.399	−0.801
AEB5	This brand contributes to my image.	3.36	1.211	−0.415	−0.706
AEB6	This brand adds to a social ‘role’ I play.	2.62	1.289	0.193	−1.062
AEB7	This brand has a positive impact on what others think of me.	2.84	1.231	0.105	−0.903
AEB8	This brand improves the way society views me.	2.56	1.287	0.274	−1.047
Brand love—BLO; Scale from 1 to 7; Cronbach’s α = 0.953.
BLO1	This is a wonderful brand.	4.28	1.701	0.105	−0.953
BLO2	This brand makes me feel good.	4.48	1.684	−0.115	−0.899
BLO3	This brand is totally awesome.	4.26	1.703	0.073	−0.941
BLO4	This brand makes me very happy.	3.86	1.703	0.223	−0.720
BLO5	I love this brand!	4.60	1.656	−0.100	−0.978
BLO6	This brand is a pure delight.	3.32	1.694	0.423	−0.493
BLO7	I am passionate about this brand.	3.26	1.694	0.519	−0.420
BLO8	I’m very attached to this brand.	3.46	1.780	0.397	−0.705
Brand loyalty—BLY; Scale from 1 to 7; Cronbach’s α = 0.882.
BLY1	This is the only brand of this product that I will buy.	2.60	1.932	1.011	−0.229
BLY2	When I go shopping, I don’t even notice competing brands.	2.54	1.888	1.097	0.016
BLY3	If my store is out of this brand, I’ll postpone buying or go to another store.	3.37	2.103	0.412	−1.183
BLY4	I’ll ‘do without’ rather than buy another brand.	2.36	1.799	1.285	0.557
Environmental cause knowledge—ECK; Scale from 1 to 5; Cronbach’s α = 0.889.
ECK1	I know a lot about environmental issues.	3.23	1.196	−0.262	−0.793
ECK2	I think I know more about environmental issues than most people.	2.67	1.183	0.198	−0.772
ECK3	When it comes to environmental issues, I really know a lot.	2.75	1.148	0.099	−0.737
Positive word-of-mouth—WOM; Scale from 1 to 7; Cronbach’s α = 0.924.
WOM1	I have recommended this brand to lots of people.	3.56	1.892	0.345	−0.945
WOM2	I ‘talk up’ this brand to my friends.	3.65	1.914	0.241	−1.046
WOM3	I try to spread the good word about this brand.	2.87	1.824	0.749	−0.441
WOM4	I give this brand tons of positive word-of-mouth advertising.	3.98	1.886	0.050	−1.071
Willingness to pay a premium—WPP; Scale from 1 to 7; Cronbach’s α = 0.962.
WPP1	I am willing to pay a higher price at this brand than at its competitors.	3.57	1.779	0.295	−0.793
WPP2	I would like to keep buying at this brand, even if other companies were cheaper.	3.60	1.762	0.285	−0.789
WPP3	For the advantages I have as a customer of this brand I would be willing to pay a higher price.	3.52	1.787	0.338	−0.792

Note. M—mean; SD—standard deviation; Sk—Asymmetry; Kr—kurtosis.

).

Table 3 lists the items used in the questionnaire for the variables in the model (self-expressive brand, brand love, brand loyalty, environmental cause knowledge, positive word-of-mouth, and willingness to pay a premium), with the mean, standard deviation, kurtosis, and asymmetry coefficients and reliability score (Cronbach’s α). The variable self-expressive brand (scale: 1–7) always shows values below 4, with AEB5 (“this brand contributes to my image”) being the item with the highest value (M = 3.36). The variables brand loyalty, positive word-of-mouth, and willingness to pay a premium (scale: 1–7) also always show values below 4, with the items with the highest value being BLY3 (“if the products of this brand are sold out in the store I go to, I postpone the purchase or go to another store”; M = 3.37), WOM2 (“I talk about this brand with my friends”; M = 3.65), and WPP2 (“I would like to buy sustainable products from this brand, even if other products are cheaper”; M = 3.60). Several items in the brand love (scale: 1–7) and environmental awareness (scale 1–5) variables have scores above 4 and 2.5, respectively, including BLO1 (“this brand is wonderful”; M = 4.28), BLO2 (“this brand makes me feel good”; M = 4.48), BLO3 (“this brand is fantastic”; M = 4.26), BLO5 (“I really like this brand”; M = 4.60), ECK1 (“I have good knowledge of environmental sustainability issues”; M = 3.23), ECK2 (“I think I know more about environmental issues than most people”; M = 2.67), and ECK3 (“I have a good understanding of environmental issues”; M = 2.75). The lowest scoring items are AEB4 (“this brand is an extension of my inner self”; M = 2.42) and BLY2 (“when I buy jeans, I don’t even look at other brands”; M = 2.54).

4.3. Instrument Validation

To validate the 30-item instrument used in the questionnaire, a principal component analysis was performed on the data from 978 participants. The adequacy assumptions of the PCA were checked beforehand. All correlations were statistically significant (p < 0.001), and the individual variables had at least one correlation coefficient greater than 0.3. On the other hand, the overall Kaiser–Meyer–Olkin measure of 0.94 and the individual KMO measures, all greater than 0.8, were excellent [81]. Bartlett’s sphericity test was statistically significant [χ²(435) = 30,514.6, p < 0.001], indicating that the data are factorable.

The principal component analysis (PCA) converged in six iterations to a structure of six components with an eigenvalue greater than 1, explaining 20.7%, 19.7%, 10.7%, 9.8%, 9.3%, and 8.6% of the total variance, respectively. A scree plot inspection suggested the six-component solution, which also met the interpretation criterion.

The six-component solution explained 78.7% of the total variance. Varimax rotation was applied to support the interpretation. The rotated solution resulted in a simple structure whose interpretation was consistent with the concepts the developed questionnaire was designed to measure, including self-expressive brands, brand love, brand loyalty, knowledge of the environmental cause, positive word-of-mouth, and willingness to pay a premium. The structural loadings (>0.6) and communalities (>0.5) of the rotated solution with Kaiser normalization are documented in

Table 4. Principal component matrix with varimax rotation for six components and communalities.

Variable	Coefficients of the Rotated Components λ						h2
	LD1	LD2	LD3	LD4	LD5	LD6
AEB1	0.834						0.772
AEB2	0.856						0.811
AEB3	0.869						0.844
AEB4	0.857						0.832
AEB5	0.632						0.541
AEB6	0.800						0.730
AEB7	0.788						0.703
AEB8	0.766						0.676
BL1		0.831					0.830
BL2		0.835					0.834
BL3		0.851					0.872
BL4		0.767					0.794
BL5		0.821					0.803
BL6		0.696					0.635
BL7		0.691					0.707
BL8		0.681					0.727
BLY1			0.856				0.816
BLY2			0.864				0.838
BLY3			0.638				0.558
BLY4			0.831				0.802
ECK1						0.815	0.762
ECK2						0.850	0.829
ECK3						0.875	0.857
WOM1				0.790			0.871
WOM2				0.806			0.870
WOM3				0.670			0.738
WOM4				0.725			0.788
WPP1					0.895		0.922
WPP2					0.907		0.934
WPP3					0.889		0.930

Note. LD—coefficients of the rotated components; h²—communalities.

. It can be seen (Table 3) that all scales have good reliability (>0.8).

Convergent and discriminant validity types were then assessed. As shown in

Table 5. Reliability and discriminant validity.

Variable	Measure	M	SD	Correlations						C.R.	AVE
				AEB	BLO	BLY	ECK	WOM	WPP
AEB	1–7	2.66	1.07	0.804						0.935	0.646
BLO	1–7	3.94	1.48	0.587 **	0.775					0.923	0.600
BLY	1–7	2.72	1.66	0.381 **	0.457 **	0.802				0.877	0.644
ECK	1–5	2.89	1.06	0.319 **	0.368 **	0.344 **	0.750			0.836	0.562
WOM	1–7	3.51	1.70	0.514 **	0.670 **	0.521 **	0.351 **	0.847		0.844	0.717
WPP	1–7	3.56	1.71	0.294 **	0.396 **	0.367 **	0.461 **	0.427 **	0.897	0.925	0.805

Note. ** p < 0.01; AEB—self-expressive brand; BLO—brand love; BLY—brand loyalty; ECK—environmental cause awareness; WOM—positive word-of-mouth; WPP—willingness to pay a premium; M—mean; SD—standard deviation; C.R.—composite reliability; AVE—average variance extracted; In bold (diagonal): square root of the AVE.

, C.R. > 0.7 and AVE > 0.5 confirm the convergent validity, and the variance shared between the variables does not exceed the square root of the AVE, confirming the discriminant validity (Table 5).

A confirmatory factorial analysis was then used to test the instrument established by the PCA. A six-factor model was found [χ²(369) = 1196.322, p < 0.001], which showed a good fit according to the following indicators: CFI = 0.973; NFI = 0.961; RMSEA = 0.048 (0.045–0.051; 90% CI); PCLOSE = 0.870; χ²/df = 3.242 (reasonable fit); SRMR = 0.069 (acceptable value). However, it was necessary to establish some correlations between item errors to obtain this model.

To test the hypotheses, a path analysis was carried out based on the structural equation model using SPSS AMOS software (Figure 2). The outcomes, detailed in Figure 2 and

Table 6. SEM results and hypothesis evaluation.

Hypothesis	Path	Hypothesis Description	β	Evaluation
H1	AEB → BLO (+)	Self-expressive brand has a positive association with brand love.	0.504 *	Supported
H2a	BLO → WOM (+)	Brand love is positively associated with positive word-of-mouth.	0.552 **	Supported
H2b	BLO → BLY (+)	Brand love is positively related to brand loyalty.	0.430 *	Supported
H2c	BLO → WPP (+)	Brand love is positively associated with the willingness to pay a premium.	0.226 **	Supported
H3a	BLY → WOM (+)	Brand loyalty is positively associated with positive word-of-mouth.	0.302 *	Supported
H3b	BLY → WPP (+)	Brand loyalty is positively associated with the willingness to pay a premium for sustainable jeans.	0.181 **	Supported
H4	ECK → WPP (+)	Knowledge of the environmental cause is positively associated with the willingness to pay a premium for sustainable blue jeans.	0.368 **	Supported

Note. β—standardized regression coefficient values; * p < 0.05; ** p < 0.01; AEB—self-expressive brand; BLO—brand love; BLY—brand loyalty; ECK—environmental cause awareness; WOM—positive word-of-mouth; WPP—willingness to pay a premium.

, present the effects of the variables and confirm all hypotheses. All examined structural relationships show positive signs and parameters, aligning with the assumptions articulated in the literature review.

Table 6 summarizes the resulting standardized regression coefficients. The strongest regressions with the dependent variables WOM and WPP are between brand love and brand loyalty and between knowledge of the environmental cause and WPP. Figure 2 also illustrates that the coefficient of determination (R²) for word-of-mouth is 0.510; in other words, both brand love and brand loyalty collectively account for 51.0% of the variance in word-of-mouth. Additionally, brand love independently expounds 20.8% of the variability in brand loyalty, whereas brand love and environmental-cause knowledge collectively explain 29.2% of the variance in the willingness to pay a premium.

4.4. Differences

The considerations drawn from the literature concerning the influence of demographic variables in word-of-mouth and willingness to pay a premium led us to explore differences between groups. Statistically significant differences were found only for the willingness to pay a premium and between generation Z and millennials, being that the pairwise comparison showed that generation Z members were more willing to pay a premium (M = 3.66 vs. 3.21, F (3, 972) = 3.547; p = 0.014; η² = 0.11).

A t-test was conducted in terms of gender, education level, and knowing or not knowing about sustainable line extensions concerning positive word-of-mouth and the willingness to pay a premium (

Table 7. Differences based on gender, education level, and knowing or not knowing about sustainable line extensions.

Variable	Group	N	M	SD	t	df	p Value	Cohen’s d
	Gender
WOM—Positive word-of-mouth.	Female	596	3.67	1.713	3.66	837	0.169	0.238
	Male	382	3.27	1.642
WPP—Willingness to pay a premium.	Female	596	3.67	1.713	3.62	976	0.934	0.096
	Male	382	3.27	1.642
	Education level
WOM—Positive word-of-mouth.	Basic and Secondary/vocational	460	3.64	1.737	2.26	949	0.067	0.145
	Higher education	518	3.40	1.653
WPP—Willingness to pay a premium.	Basic and Secondary/vocational	460	3.55	1.770	−0.23	976	0.046	0.015
	Higher education	518	3.57	1.662
	Know/not know about sustainable line extensions
WOM—Positive word-of-mouth.	Not know	559	3.16	1.624	−7.74	976	0.169	−0.394
	Know	419	3.98	1.679
WPP—Willingness to pay a premium.	Not know	559	3.28	1.596	−6.11	976	0.001	−0.500
	Know	419	3.94	1.790

Note: N—frequency; M—mean; SD—standard deviation; t—Student’s t; df—degrees of freedom; Cohen’s d—effect size; statistically significant values shown in bold.

). The only significant differences found were in the willingness to pay a premium; consumers with higher education levels were marginally more willing to pay a premium for sustainable blue jeans (M = 3.57 vs. 3.55, t (837) = 3.66, p = 0.169), while those who were aware of sustainable line extensions were more willing to pay a premium than their counterparts (M = 3.94 vs. 3.28, t (976) = 6.11, p = 0.001).

5. Discussion

The results began with a general description of the sample, whose respondents were mostly young, active women with higher education, as well as their habits, which showed that most consumers buy blue jeans with some frequency (more than three pairs in two years) and mainly in retail stores. They also confirmed that identification, measured by the self-expressive brand variable (AEB), has a positive association with brand love (BLO), which is in line with the literature [24,27,34,35]. The results obtained with AEB showed that the dimension of consumer identification with the brand, i.e., the extent to which consumers incorporate their favorite jeans brand into their self-concept, is not particularly strong (M = 2.64), except for the consideration that this brand contributes to their image (thereby showing social concern). These scores were lower than those obtained for the brand love variable, which also occurred in the study by Carrol and Ahuvia [27]. At first glance, this result might suggest that identification is not as strong a determinant of brand love in this case as might be expected—perhaps because blue jeans are seen more as a utilitarian product and less as a form of self-expression. In any case, identification was well correlated with brand love, with an overall effect of 0.50, as measured by the structural equation model, consistent with the findings from other comparable studies [24,27].

Brand love was one of the highest scoring variables in this study (M = 3.94), suggesting that blue jeans brands do indeed evoke such feelings. This was likely the result of considering brand love a unidimensional construct, although there are other individual dimensions of brand love that were not addressed in this study (e.g., the hedonic versus utilitarian nature of the product and trust in the brand).

The model also shows that brand love is positively associated with positive word-of-mouth (consistent with [27,46,47]) and the willingness to pay a premium for sustainable blue jeans (consistent with [48,50,51]). This association between brand love and positive word-of-mouth is comparable to the results obtained by Albert and Merunka [24] and Carrol and Ahuvia [27]. The effect obtained from brand love on willingness to pay a premium was lower than that recorded for positive word-of-mouth and lower than that obtained by Albert and Merunka [24]. In part, this effect can be attributed to the fact that the sample was Portuguese, with an average age of 30, which was lower than the sample in Albert and Merunka’s [24] study, which was composed of French participants with an average age of 36. On the one hand, it would be expected that younger consumers would be less willing to pay more and that Portuguese consumers would have less purchasing power than French consumers. On the other hand, it is possible that consumers who are not aware of sustainable alternatives to blue jeans brands are not particularly motivated to spread the word or even to pay more for sustainable jeans; since more than half of the sample had this status, this justification is plausible and is reflected in the differences reported in Table 7 (participants who are aware of sustainable alternatives always show higher values than those who are not aware for all independent and dependent variables). Consistent with several authors (e.g., [27,38,39,44,45,54]), loyalty was positively associated with brand love, positive word-of-mouth, and willingness to pay a premium for sustainable jeans [24].

The environmental cause knowledge (ECK) variable was meant to measure the respondents’ level of knowledge about environmental sustainability issues in order to analyze whether this dimension is related to their willingness to pay a premium for sustainable blue jeans. The sample scored above average for this variable, indicating that most participants in the study identified with the cause. However, it is important to note that 57.2% of the sample did not know if their favorite jeans brand offered sustainable clothing. This finding suggests the need for caution in interpreting the results; on average, we are dealing with a consumer who claims to be concerned about the environment but in practice does not know about (or has little interest in knowing if there are) sustainable product alternatives. The test of differences between those who know and those who do not know about sustainable alternatives to jeans showed that the level of awareness of the environmental issue was significantly higher among consumers who knew about alternatives, which can be understood if one assumes that if consumers are more aware of the issue, they will look for sustainable products or pay more selective attention to them; consequently, they will be more willing to pay a premium for them. However, the results showed that ECK had a positive but very marginal relationship with this aspect.

Regarding gender, only females had higher scores than males for all variables, which was consistent with the expectations reported in the literature [66,68,69], although not significant. Regarding education levels, the literature does not provide much guidance on what to expect, other than that there will be positive differences in the propensity to value the purchasing of sustainable products. In this study, a single significant difference was found in terms of education level, as consumers with higher education levels were also more willing to pay a premium for sustainable blue jeans than their counterparts, a result also previously reported by several authors [68,69,76], although in the absence of other differences, the results were closer to Rahim et al. [77], who found no significant differences in consumer behavior toward sustainable products, namely in terms of age or education level. However, members of generation Z were found to be more willing to pay a premium for sustainable blue jeans than millennials. This result is in line with Pauluzzo and Mason [74], in that millennials claim to be aware of environmental issues and willing to support them and pay more for sustainable products, although this is not reflected in the actual behavior of these consumers.

6. Conclusions

The work carried out in this study allowed us to find a model that fit the data for 978 respondents to verify the results reported in the literature among Portuguese consumers of blue jeans, namely the positive associations of identification with brand love; of brand love with brand loyalty, positive word-of-mouth, and willingness to pay a premium for sustainable blue jeans; and of knowledge of the environmental cause with willingness to pay a premium for sustainable blue jeans. It was also concluded that there were no significant gender differences in terms of positive word-of-mouth and willingness to pay a premium for sustainable blue jeans. Members of generation Z and consumers with higher education levels are more willing to pay a premium for sustainable blue jeans than their counterparts.

It was also found that consumers who were aware of sustainable blue jeans alternatives from their preferred brands had significantly higher scores for all variables in the model, suggesting that this awareness may be associated with greater knowledge of the environmental cause, which is critical in explaining the greater levels of identification, brand love, and brand loyalty, and the resulting intention to spread the good word and willingness to pay a premium for sustainable blue jeans.

The positive impacts of brand love on brand loyalty, word-of-mouth, and willingness to pay a price premium was further acknowledged according to the literature findings. To the best of the authors’ knowledge, this study is the first to incorporate knowledge of environmental causes in a model that relates brand love to brand loyalty and the latter to positive word-of-mouth and willingness to pay a premium, as tested by Caroll and Ahuvia [27] and Albert and Merunka [24], applied here to the Portuguese market and focused on sustainable blue jeans. This approach, thus, incorporates Bagozzi et al.’s [26] suggestion to develop models in which brand love is central to other dimensions, thereby contributing to the academic literature. The findings also have practical implications for blue jeans brands as they enhance the importance of creating awareness of the existence of sustainable extension lines, as well as of conveying a true environmental concern to capture environmentally driven consumers that would be willing to pay a premium for sustainable blue jeans, namely by focusing on creating increased proximity to consumers by enhancing their values and seeking to link the brand to intrinsic benefits and environmental stakes.

It may be interesting to replicate this proposed model with other products and in other markets with fewer sample limitations, thereby overcoming the limitation of a convenience sample. In future studies, better results may be obtained when all participants respond to the same brand [26]. Treating brand love as a multidimensional variable could reveal subdimensions that are “hidden” in the approach as a unidimensional variable, providing new opportunities for marketing differentiation. Finally, it would be helpful to include other determinants of brand love and outcomes beyond positive word-of-mouth and willingness to pay a premium (e.g., purchase intention).