A Study on the Driving Factors of Continued Use of Sustainable Ready-to-Drink Packaging: The Moderating Roles of Perceived Sustainability and Perceived Value Fit

Abstract

This study, based on the Decomposed Theory of Planned Behavior (DTPB), constructs and validates a systematic model to explore the key drivers influencing consumers’ continuous usage intention of sustainable Ready-to-Drink (RTD) beverage packaging. The model includes perceived value and social normative paths, introducing perceived sustainability (PS) and perceived value fit (PVF) as moderators to reveal the role of contextual perceptions in green consumption decision-making. Empirical results show that all conventional path hypotheses (H1–H6) are supported. Among the moderating effect hypotheses, H7b, H9a, and H10c are not supported, while the rest hold. Theoretical implications include the following: Perceived Usefulness (PU) and Perceived Enjoyment (PE) significantly and positively influence consumer satisfaction (SA), consistent with the Expectation Confirmation Model (ECM). Both external influence (EI) and interpersonal influence (II) significantly enhance subjective norms (SN), aligning with TPB theory. Self-efficacy (SE) and facilitating conditions (FA) positively affect perceived behavioral control (PBC), consistent with the DTPB model. Satisfaction, subjective norms, and perceived behavioral control significantly predict continuous usage intention (UI), with satisfaction showing the strongest effect, highlighting the importance of positive initial experiences for green behavior continuation.

1. Introduction

With the intensification of environmental challenges, the ecological impact of packaging waste has emerged as a global concern [1]. As a key segment of fast-moving consumer goods, Ready-to-Drink (RTD) beverages face particularly pressing issues regarding the sustainability of their packaging. Traditional packaging methods often result in significant resource consumption and environmental pollution across their production, usage, and disposal stages, prompting both academia and industry to explore greener and more sustainable packaging solutions [2,3]. Sustainable packaging, which integrates environmental protection, resource efficiency, and economic viability, has increasingly become a crucial pathway for promoting green consumption and advancing the circular economy [4].

Despite continuous progress in the design and technology of sustainable packaging, considerable variation remains in consumer acceptance and sustained usage behaviors [5]. The underlying mechanisms by which cognitive evaluations, emotional responses, and social influences shape the adoption of sustainable packaging are not yet fully understood [6]. In the RTD beverage sector—a highly competitive market that heavily relies on packaging differentiation—understanding the internal and external drivers of consumers’ continued choice of sustainable packaging holds significant theoretical and practical implications [7]. Existing research, primarily grounded in the Theory of Planned Behavior (TPB) and its extended models [8,9], has examined green consumer behavior by emphasizing variables such as perceived behavioral control, subjective norms, and attitudes [10]. More recently, the Decomposed Theory of Planned Behavior (DTPB) has refined the concept of behavioral control by incorporating key components such as self-efficacy and facilitating conditions, thereby enhancing the explanatory power of the model in the context of pro-environmental behaviors [11]. In addition, the Expectation Confirmation Model (ECM) offers a valuable perspective for understanding continued usage intentions, highlighting satisfaction as a central mediating variable that bridges perceived value and behavioral intention [12].

Anchored in the framework of the DTPB, this study integrates two key dimensions of perceived value—perceived usefulness and perceived enjoyment—alongside external influences and interpersonal influences as mechanisms of social and environmental impact, as well as self-efficacy and facilitating conditions, to comprehensively investigate the drivers of consumers’ continued usage intention toward sustainable RTD packaging. Furthermore, the study introduces perceived sustainability and perceived value fit as moderating variables to explore their roles in shaping these relationships, thereby addressing existing gaps in the literature concerning moderating mechanisms. By constructing a systematic theoretical model and validating it with empirical data, this research not only advances understanding of consumer behavior in the context of sustainable packaging but also provides a scientific basis for packaging design, market promotion, and policy development. The findings promote the adoption and diffusion of sustainable packaging and support the transition toward sustainable green consumption.

2. Literature Review and Hypotheses Development

2.1. Sustainable Packaging and Sustainable Ready-Made Beverage Packaging

Due to its complexity and multidimensional nature, the concept of sustainable packaging has yet to reach a universally accepted definition at the international level [13]. Currently, two of the most influential definitions are proposed by the Sustainable Packaging Alliance (SPA) and the Sustainable Packaging Coalition (SPC) [14]. The SPA identifies four core principles of sustainable packaging—effectiveness, efficiency, cyclicality, and clean production—emphasizing the overall performance of the packaging system. In contrast, the SPC, in its 2005 definition, describes sustainable packaging as one that “reduces environmental impact to the greatest extent possible while ensuring product quality and user convenience” [13]. Compared with SPA’s approach, the SPC’s definition is more inclusive, as it not only focuses on functional efficiency but also highlights the importance of renewable energy usage and the preferential selection of environmentally friendly materials [13,14].

From a macro perspective, sustainable packaging should adopt a systems approach, aiming to generate environmental and social value throughout the entire product life cycle [15]. From a micro perspective, the emphasis lies on resource conservation and the application of eco-friendly materials. Based on this understanding, this study defines sustainable packaging as a packaging approach that reduces resource consumption and environmental burden through the use of environmentally responsible materials and energy-saving processes, while maintaining economic viability and functional performance [16]. Moreover, the principle of sustainability should be embedded across all stages of the packaging life cycle, including production, usage, and post-consumption treatment, in order to achieve a truly sustainable packaging system [17,18].

2.2. Extension of the DTPB Mode

2.2.1. Perceived Usefulness, Perceived Enjoyment, and Satisfaction

In the context of sustainable packaging research, satisfaction is commonly defined as consumers’ cognitive evaluation of whether the perceived value of sustainable RTD packaging aligns with their prior expectations. This definition aligns closely with the core tenets of Expectation Confirmation Theory (ECT), which posits that when a product’s actual performance meets or exceeds consumer expectations, it enhances satisfaction and, in turn, strengthens the intention to continue using the product [19]. In the study, Oliver (1980) emphasizes that satisfaction arises from a cognitive comparison between expectations and actual performance; when the experience surpasses expectations, it results in positive confirmation, thereby increasing satisfaction [19]. Building on this foundation, Bhattacherjee (2001) developed the Expectation Confirmation Model (ECM), further demonstrating the joint effects of perceived usefulness and confirmation on both satisfaction and continued usage intention [12].

Moreover, studies have shown that consumer satisfaction is influenced not only by their cognitive evaluation of a product or service but also by a variety of external factors. Elements such as brand image, perceived quality, and service experience have all been empirically verified as positive contributors to satisfaction. Alhaddad (2015) argues that brand image influences brand loyalty via perceived quality, while perceived quality enhances loyalty by improving satisfaction [20]. Within the domain of green consumption, the formation mechanism of satisfaction becomes even more complex, with emotional experience and functional utility serving as key drivers. For example, Lin (2023) found that green enjoyment and intrinsic green motivation significantly boost green purchase intention, with satisfaction acting as a mediating factor [21]. Wu & Long (2024) further proposed that perceived usefulness of information can indirectly enhance environmentally responsible purchase intention by strengthening green trust [22].

It is thus evident that in the context of sustainable packaging research, perceived usefulness (PU) and perceived enjoyment (PE) are two key antecedents of consumer satisfaction (SA), both of which carry significant theoretical value. Specifically, PU refers to the extent to which consumers believe that using sustainable RTD packaging enhances their quality of life, convenience, or efficiency. Numerous studies have demonstrated that PU not only exerts a significant positive impact on SA, but also further influences continued usage intention (UI) [12]. In the context of sustainable packaging, the green attributes of packaging have been shown to evoke positive emotional responses and increase SA, thereby strengthening consumers’ purchase intentions [23]. In addition, both green packaging and consumers’ perceived efficacy can promote green consumption behaviors through the mediating pathway of green satisfaction [24].

On the other hand, PE refers to the intrinsic pleasure and subjective enjoyment that consumers experience when using sustainable RTD packaging—an affective response that is independent of the product’s functionality or instrumental value [25]. In consumer behavior research, PE has been widely recognized as a significant predictor of SA; when consumers derive enjoyment from product usage, they are more likely to form positive overall evaluations [26]. Moreover, such emotional responses not only enhance immediate satisfaction, but also strengthen emotional attachment and improve user experience, thereby further promoting continued usage intention. Accordingly, we propose the following:

H1a: 

The PU of sustainable RTD packaging positively influences consumer SA.

H1b: 

The PE of sustainable RTD packaging positively influences consumer SA.

2.2.2. External Influences, Interpersonal Influences, Subjective Norms

In the field of green consumption research, subjective norm (SN) is widely recognized as one of the key determinants influencing consumers’ green purchase intentions. According to the TPB, SN refers to the perceived social expectations and normative pressures from others or social groups during an individual’s decision-making process [10]. In the context of green consumption, SNs are typically shaped by two core dimensions: interpersonal influence and external influence.

Interpersonal influence (II) stems from close referents—such as family members, friends, or colleagues—who express approval, offer encouragement, or reinforce particular behaviors. Prior research has shown that such proximal social interactions can significantly strengthen individuals’ subjective norms and thereby foster the formation of green purchase intentions [27]. External influence (EI), on the other hand, refers to broader societal and environmental stimuli, including media exposure, social media dissemination, and government advocacy. Xu et al. (2022) found that environmental awareness, descriptive norms, and self-efficacy all exert significant positive effects on green purchasing intentions [28]. Similarly, Xie and Madni (2023) noted that pro-environmental messaging disseminated via social media can enhance consumers’ subjective norms and green value perceptions, thereby indirectly increasing their intention to engage in sustainable behaviors [29].

Within the research context of sustainable packaging, media campaigns, policy interventions, and other external forces play a crucial role in shaping social norms and guiding public awareness. These external influences not only reinforce subjective norms but also increase consumers’ acceptance and adoption intention toward sustainable RTD packaging [27]. In addition, Wang (2024) highlights that consumers’ social identity significantly heightens their sensitivity to subjective norms, further promoting their inclination toward green consumption [30]. Accordingly, we propose the following:

H2a: 

EI positively affects consumers’ SNs toward sustainable RTD packaging.

H2b: 

II positively affects consumers’ SNs toward sustainable RTD packaging.

2.2.3. Self-Efficacy, Facilitation, and Perceived Behavioral Control

In green consumer behavior research, perceived behavioral control (PBC) is a core construct within the TPB. It refers to an individual’s subjective assessment of how easy or difficult it is to perform a particular behavior [10]. Within the context of sustainable packaging, PBC reflects consumers’ perceived levels of personal capability (i.e., self-efficacy) and external enabling conditions (i.e., facilitating conditions). According to the DTPB, PBC can be further decomposed into two key dimensions: self-efficacy and facilitating conditions [31].

Self-efficacy (SE) refers to an individual’s confidence in their own ability to perform a given behavior and their personal judgment about that ability. Facilitating conditions (FA), on the other hand, capture the degree to which an individual perceives they possess sufficient resources, opportunities, and environmental support to carry out the behavior. In the context of green consumption, a growing body of research has confirmed the significant influence of both SE and FA on PBC. For example, Yadav and Pathak (2017) found that SE was a significant positive predictor of green purchase intentions among consumers in developing countries [32]. Similarly, Wang et al. (2021) highlighted that the accessibility and ease of use of recyclable packaging directly enhance consumers’ intention to adopt such products [33].

Further research has shown that PBC also serves as a mediating mechanism through which environmental knowledge influences green behavioral intentions. In an empirical study of female professionals in Mexico, Gutiérrez-Martínez (2022) found that environmental knowledge could enhance green behavioral intention indirectly by increasing PBC [34]. In addition, PBC often operates in conjunction with attitudes and subjective norms to shape individuals’ intentions toward sustainable behaviors [35], and it has demonstrated significant mediating effects in the contexts of green cosmetics and organic food consumption [36,37].

In the specific context of sustainable RTD packaging, SE reflects consumers’ confidence in their ability to properly use, sort, and dispose of sustainable packaging. FA refers to the availability and ease of use of the packaging, as well as the completeness of supporting policies, infrastructure, or technologies.

H3a: 

SE positively influences consumers’ PBC regarding sustainable RTD packaging.

H3b: 

FA positively influences consumers’ PBC regarding sustainable RTD packaging.

2.3. Continuance Usage Intention

In this study, continuance usage intention (UI) is defined as an individual’s willingness to repeatedly engage in a particular behavior following initial adoption [12]. Specifically, it refers to consumers’ inclination to continue selecting and using sustainable Ready-to-Drink (RTD) packaging after their initial experience.

The formation of continuance UI primarily draws upon the Information Systems Continuance Model (ISCM) and the Expectation Confirmation Model (ECM) [12,26]. According to ECM, users evaluate a product or service based on Expectation Confirmation and perceived usefulness after initial use, which in turn affects their satisfaction and subsequently shapes their willingness to continue using it [26]. Thong et al. (2006) also demonstrated in the context of mobile internet services that social–cognitive variables such as PBC and SNs significantly predict continuance usage intention [26].

In the field of green consumption, relevant studies have further validated that satisfaction, SNs, and PBC are key antecedents of consumers’ continuance usage intention [32,38]. Li et al. (2021) found that SA and SNs influence continuance usage intention indirectly through social identity mechanisms, while PBC primarily exerts its influence through consumers’ perception of available resources and opportunities [39]. Accordingly, we propose the following:

H4: 

SA positively influences consumers’ UI toward sustainable RTD packaging.

H5: 

SNs positively influence consumers’ UI toward sustainable RTD packaging.

H6: 

PBC positively influences consumers’ UI toward sustainable RTD packaging.

2.4. Moderating Effects of Perceived Sustainability

Perceived sustainability (PS) refers to the subjective interpretation and cognitive evaluation formed by individuals after exposure to sustainability-related information and experiences regarding a product or behavior, which subsequently guides their behavioral responses [40]. PS emphasizes individuals’ cognitive interpretation of their own environmentally friendly behaviors within specific socio-cultural contexts, rather than a direct reflection of the product’s objective environmental performance. On one hand, PS is primarily influenced by external cues such as eco-labels, brand image, marketing messages, and media communication [41]; Boesen et al. (2019) pointed out that this subjective perception sometimes does not fully align with the actual environmental performance [42]. On the other hand, Reckwitz (2002) argued that PS is embedded in everyday social practices, reinforcing individuals’ environmental responsibility awareness through behavioral habits and cultural perspectives [43]. Empirical studies by Steenis et al. (2017) and Liang et al. (2022) further demonstrate that PS can moderate the relationship between perceived behavior and sustainable practices, thereby enhancing the motivation for pro-environmental behavior [44,45]. Then, we hypothesize the following:

H7a: 

PS moderates the relationship between PU and SA; higher PS strengthens this effect.

H7b: 

PS moderates the relationship between PE and SA; the higher the PS, the stronger the effect.

H8a: 

PS moderates the effect of EI on SNs; the effect is stronger under higher PS.

H8b: 

PS moderates the effect of II on SNs; higher PS enhances this relationship.

H9a: 

PS moderates the link between SE and PBC; the association grows with higher PS.

H9b: 

PS moderates the relationship between FA and PBC; the higher the PS, the stronger the effect.

2.5. Moderating Effects of Perceived Value Fit

In recent years, TPB has remained the dominant framework for predicting consumer behavioral intentions, particularly in the contexts of green consumption and digital usage [46,47]. Traditionally, TPB posits that behavioral intention is determined by three antecedents: attitude toward the behavior, subjective norms, and perceived behavioral control. However, as research increasingly focuses on post-adoption behavior and users’ continued usage intentions, some scholars have proposed replacing general attitude with user satisfaction to better capture users’ evaluative experiences following initial adoption [48,49].

With ongoing theoretical refinement, perceived value fit (PVF)—defined as the alignment between an individual’s personal values and those projected by a service, platform, or brand—has emerged as a critical factor influencing behavioral outcomes. Studies indicate that when consumers perceive a high degree of value congruence, their satisfaction tends to increase, accompanied by stronger behavioral commitment [50,51]. This value congruence not only shapes internal evaluations but also appears to enhance the influence of other predictors related to perceived behavioral control on behavioral intention, serving as a contextual moderator [51,52].

For example, La Barbera and Ajzen (2020) demonstrated an interaction between subjective norms and perceived behavioral control, suggesting that predictors of PBC may exert interactive effects on behavioral intention [53]. Building on this interactive framework, Ghorban et al. (2024) found that individual-level traits such as evaluation needs and self-referencing can moderate the strength of TPB pathways, particularly between attitude-related constructs and behavioral intention [54]. These findings support the conceptual plausibility of perceived value congruence functioning as a moderator within the TPB framework. Specifically, when users perceive a high alignment between their own values and those of the product or platform, they are more likely to translate satisfaction into continued use, experience stronger normative social pressure, and feel more confident in their ability to perform the behavior. Conversely, lower levels of value congruence may weaken the influence of these psychological drivers.

H10a: 

PVF moderates the relationship between user SA and UI, such that this relationship is stronger when PVF is higher.

H10b: 

PVF moderates the relationship between SNs and UI, such that this relationship is stronger when PVF is higher.

H10c: 

PVF moderates the relationship between PBC and UI, such that this relationship is stronger when PVF is higher.

2.6. Proposed Research Model

Figure 1 shows the research model.

3. Data and Methodologies Employed

3.1. Research Subject and Measurement Items

The research subject of this study is Starbucks’ sustainable beverage packaging. Data were collected from respondents across various regions, predominantly from Central China, followed by China. The questionnaire comprises two main sections. The first section collects respondents’ demographic information, and the second section assesses the measurement indicators of each observed variable, consisting of 45 items.

3.2. Data Collection and Sample

The questionnaire survey was conducted from 5 January 2025 to 16 May 2025. Prior to the formal investigation, participants were clearly informed of the purpose and procedure of the study. After fully understanding the research process, participants gave verbal consent to take part in the study.

The formal survey was distributed and collected via the Wenjuanxing (问卷星) platform between April and May 2025, with a total of 547 questionnaires distributed. Before data analysis, several exclusion criteria were adopted: respondents who had never used sustainable beverage packaging were excluded, along with those who gave identical responses across all items or completed the questionnaire in less than 60 s. Ultimately, 443 valid questionnaires were obtained, representing an effective response rate of 81%.

4. Results

4.1. Sample Profile

A summary of participants’ basic information can be seen in

Table 1. Demographics profile of the sample (n = 443).

Variable	Category	Frequency	%
Gender	Male	156	35.21
	Female	287	64.79
Age	<18	10	2.26
	18–25	307	69.3
	26–30	77	17.38
	31–40	27	6.09
	41–50	17	3.84
	51–60	4	0.9
	>60	1	0.23
Education	High school and below	10	2.26
	Junior college	102	23.02
	College	218	49.21
	Post-graduate and beyond	113	25.51
How often do you encounter sustainable beverage packaging?	<1	40	8.28
	1–5	185	38.30
	5–10	98	20.29
	>10	160	33.13

:

4.2. Confirmatory Factor Analysis

This study employed AMOS 24.0 to conduct confirmatory factor analysis (CFA) in order to assess the convergent and discriminant validity of the scales. The convergent validity of the scales is as follows.

Convergent validity was evaluated using three criteria: (1) all standardized factor loadings (standard regression weights) should exceed 0.5; (2) composite reliability (CR) should be greater than 0.7; and (3) the average variance extracted (AVE) should be greater than 0.5. From

Table 2. Convergent validity.

Variable	Items	Factor Loading	Cronbach’s α	CR	AVE	Mean	S.D.
Perceived Usefulness	PU1	0.857	0.874	0.876	0.639	5.455	1.242
	PU2	0.823
	PU3	0.773
	PU4	0.740
Perceived Enjoyment	PE1	0.787	0.840	0.841	0.572	4.911	1.172
	PE2	0.761
	PE3	0.805
	PE4	0.663
External Influence	EI1	0.838	0.855	0.856	0.598	5.101	1.258
	EI2	0.742
	EI3	0.754
	EI4	0.755
Interpersonal Influence	II1	0.783	0.864	0.865	0.616	5.022	1.186
	II2	0.821
	II3	0.782
	II4	0.753
Self-efficacy	SE1	0.763	0.867	0.869	0.625	4.990	1.187
	SE2	0.814
	SE3	0.846
	SE4	0.735
Facilitation	FA1	0.779	0.886	0.887	0.662	4.852	1.314
	FA2	0.841
	FA3	0.830
	FA4	0.802
Satisfaction	SA1	0.828	0.902	0.903	0.652	5.115	1.244
	SA2	0.821
	SA3	0.748
	SA4	0.834
	SA5	0.802
Subjective Norms	SN1	0.838	0.885	0.886	0.661	4.944	1.269
	SN2	0.806
	SN3	0.773
	SN4	0.834
Perceived Behavioral Control	PBC1	0.700	0.873	0.877	0.641	4.981	1.258
	PBC2	0.841
	PBC3	0.833
	PBC4	0.821
Continued Usage Intention	UI1	0.768	0.842	0.845	0.577	5.084	1.179
	UI2	0.697
	UI3	0.746
	UI4	0.822
Perceived Sustainability	PS1	0.786	0.903	0.906	0.659	5.770	1.109
	PS2	0.840
	PS3	0.889
	PS4	0.737
	PS5	0.798
Perceived Value Fit	PVF1	0.824	0.916	0.917	0.691	5.317	1.147
	PVF2	0.898
	PVF3	0.899
	PVF4	0.736
	PVF5	0.787

, we can see that the overall scale has a relatively ideal convergent validity [55]. Based on this, a further examination of discriminant validity is shown in

Table 3. Discriminant validity.

	PU	PE	EI	II	SE	FA	SA	SN	PBC	UI	PS	PVF
PU	0.799
PE	0.637	0.756
EI	0.429	0.503	0.773
II	0.523	0.561	0.698	0.785
SE	0.410	0.533	0.599	0.578	0.791
FA	0.475	0.431	0.622	0.621	0.572	0.814
SA	0.526	0.545	0.586	0.668	0.534	0.503	0.807
SN	0.492	0.488	0.646	0.643	0.536	0.557	0.678	0.813
PBC	0.429	0.482	0.546	0.454	0.608	0.528	0.549	0.442	0.801
UI	0.515	0.616	0.571	0.613	0.449	0.498	0.648	0.544	0.492	0.760
PS	0.514	0.431	0.435	0.548	0.381	0.447	0.413	0.448	0.276	0.445	0.812
PVF	0.393	0.383	0.309	0.381	0.329	0.299	0.476	0.465	0.429	0.550	0.369	0.831

(Note: The bold text above the diagonal shows the square root of AVE, and the lower triangle shows the correlations between latent variables. All correlations are smaller than the corresponding AVE square roots, indicating good discriminant validity.).

:

The correlation coefficients among latent variables were all lower than the square root of the corresponding AVE values, indicating good discriminant validity. From Table 3, we can see that discriminant validity among the variables meets the requirements [56].

4.3. Structural Equation Modeling

The analysis above confirmed that the reliability and validity all meet the requirements. Then, we utilize AMOS 24.0 to construct the SEM diagram. For results, see Figure 2 and

Table 4. Model fit.

Classification	X2/df	RMSEA	IFI	TLI	CFI	GFI	AGFI
Criteria	<3	<0.08	>0.9	>0.9	>0.9	>0.5	>0.5
Value	2.103	0.050	0.927	0.921	0.927	0.748	0.801

below:

Table 4 shows that all indicators meet the respective model fit criteria. Based on this, further path analysis was conducted; see

Table 5. SEM results.

H	Path			β	B	S.E.	C.R.	p	Supported
H1a	SA	←	PU	0.279	0.273	0.061	4.480	***	Yes
H1b	SA	←	PE	0.428	0.448	0.069	6.512	***	Yes
H2a	SN	←	EI	0.385	0.373	0.065	5.757	***	Yes
H2b	SN	←	II	0.399	0.442	0.075	5.924	***	Yes
H3a	PBC	←	SE	0.467	0.464	0.063	7.375	***	Yes
H3b	PBC	←	FA	0.274	0.253	0.054	4.722	***	Yes
H4	UI	←	SA	0.457	0.388	0.045	8.590	***	Yes
H5	UI	←	SN	0.221	0.182	0.042	4.302	***	Yes
H6	UI	←	PBC	0.194	0.185	0.049	3.790	***	Yes

Note: *** p < 0.001.

.

Table 5 shows that all the hypotheses are supported. On this basis, further tests will be conducted on the mediating and moderating effects.

4.4. Moderating Effect

Last, we tested the moderating effect of the two factors. First, we examined the moderating role of PS between SA and PU/PE, SN and EI/EE, and PBC and SE/FA. The results tell that PS positively moderates the relationship between PU and SA (β = 0.108, SE = 0.025, p < 0.05), as illustrated in Figure 3, validating Hypothesis H7a, and no significant interaction was found between PE and SA (β = 0.058, SE = 0.028, p > 0.05), so Hypothesis H7b is not supported. And PS positively moderates the relationship between EI and SN (β = 0.095, SE = 0.028, p < 0.05) and II and SN (β = 0.126, SE = 0.030, p < 0.01), as shown in Figure 4 and Figure 5, which validate Hypotheses H8a and H8b. PS also positively moderates FA and PBC (β = 0.143, SE = 0.029, p < 0.01), as illustrated in Figure 6, supporting H9b, while no significant interaction was found between SE and PBC (β = 0.022, SE = 0.036, p > 0.05); thus, Hypothesis H9a is not supported.

We also tested the moderating role of PVF between SA, SN, PBC, and UI. The results reveal a positive interaction between SA and PVF on UI (β = 0.146, SE = 0.029, p < 0.001), as shown in Figure 7, which validates Hypothesis H10a. The interaction between SN and PVF on UI (β = 0.155, SE = 0.025, p < 0.001) is positive as well, as shown in Figure 8, supporting H10b. However, no significant interaction was shown between PBC and PVF on UI (β = 0.045, SE = 0.028, p > 0.05); thus, Hypothesis H10c is not supported.

5. Conclusions, Discussion, and Implications

5.1. Conclusions and Discussion

This study, grounded in the DTPB, constructs and validates a systematic model to explore the key drivers influencing consumers’ continued use intention of sustainable RTD packaging. The model incorporates perceived value and social normative pathways, and introduces perceived sustainability and perceived value fit as moderating variables to uncover the role of contextual perceptions in green consumption decision-making. Based on the empirical analysis, all baseline path hypotheses (H1–H6) were supported, while among the moderating effect hypotheses, H7b, H9a, and H10c were not confirmed; the remaining moderating hypotheses were supported. The theoretical implications of the findings can be summarized as follows:

First, the results show that both PU and PE have significant positive effects on consumer SA, supporting Hypotheses H1a and H1b. This is consistent with Bhattacherjee’s (2001) Expectation Confirmation Model, which posits that after initial use, consumers form satisfaction evaluations based on the product’s functional value and emotional experience [12]. If RTD packaging can meet consumer needs in terms of convenience, environmental friendliness, and aesthetic appeal, it can enhance satisfaction. Notably, perceived enjoyment—an affective driver—also plays a crucial role in sustainable packaging consumption, indicating that green consumer behavior is not solely based on rational judgment but also involves significant emotional factors.

The results also support H2a and H2b, indicating that EI and II significantly enhance consumers’ SNs. This is consistent with Ajzen’s (1991) TPB framework, where individuals’ behavioral decisions are substantially affected by others’ expectations and social norms [10]. In the context of sustainable packaging, mainstream media’s green advocacy, environmental trends on social platforms, and environmental behavior role models from family members and colleagues may all shape consumers’ perceptions of appropriate behavior, thereby increasing social pressure and conformity motivation for green actions.

At the level of perceived behavioral control, both SE and FA significantly and positively influence PBC, thereby supporting Hypotheses H3a and H3b. This indicates that when consumers believe they have the capability to properly use and manage sustainable packaging, and when relevant facilities (such as recycling systems, signage, and operation guidelines) are sufficiently accessible and convenient, their sense of control over performing the behavior is enhanced. This finding is consistent with Taylor and Todd’s (1995) DTPB model predictions and underscores that both perceived ability and actual environmental support are indispensable [31].

Regarding the effects of mediating variables on continued usage intention, the results reveal that satisfaction (H4), subjective norms (H5), and perceived behavioral control (H6) all exert significant positive influences on consumers’ intention to continue usage (UI), validating the key structural paths of the TPB model. This suggests that consumers are likely to develop long-term adoption intentions only when they are satisfied with their current packaging experience, perceive social encouragement, and feel capable of performing the behavior. Among these, satisfaction has the strongest effect, highlighting that the fundamental driver of sustained green behavior lies in a positive initial usage experience rather than solely social approval or behavioral capability.

In the moderating pathways of perceived sustainability, PS was found to exert a significant positive moderating effect on most variable relationships. Hypothesis H7a was supported, aligning with previous research findings [41], indicating that under conditions of higher PS, the positive effect of PU on SA is amplified. This suggests that when consumers clearly perceive the environmental value of packaging, the satisfaction derived from its functional benefits is further strengthened. However, H7b was not supported, which contrasts with existing studies [43]. This result implies that the relationship between PE and SA is not significantly moderated by PS. A possible explanation is that the enjoyment experience is more likely derived from aspects such as design, tactile feel, or user interaction of the packaging, which are less strongly associated with the perception of its sustainability attributes. Therefore, this influence pathway is more driven by emotional intuition than by environmental cognition. Both H8a and H8b were supported, consistent with previous studies [44], indicating that the impact of both external environmental influence and interpersonal influence on SNs becomes more pronounced in high-PS contexts. In other words, once consumers recognize the sustainability of a product, they are more receptive to social normative cues regarding the appropriateness of green behaviors. H9a was not supported, indicating that PS did not strengthen the relationship between SE and PBC, challenging prior research [45]. This may be due to the fact that SE is an internal cognitive belief, which is relatively independent of external product attributes such as sustainability. Conversely, H9b was supported, consistent with earlier findings [57], showing that PS can enhance the positive effect of facilitating conditions on PBC. This suggests that when consumers perceive a high level of sustainability, they become more attentive to the ease of using sustainable packaging, which in turn reinforces their behavioral control beliefs.

Finally, PVF was found to significantly moderate the effects of satisfaction (H10a) and subjective norms (H10b) on continuance usage intention, indicating that when consumers perceive a high degree of alignment between brand values and their personal values, the influence of satisfaction and social norms on behavioral intention is notably strengthened—consistent with previous research [50,51]. This suggests that if a brand can articulate a clear sustainability value proposition that resonates with the values of its target consumers, it can substantially enhance the stickiness and continuity of green behaviors. However, H10c was not supported, as PVF did not moderate the relationship between PBC and UI, which diverges from existing findings [53]. This result implies that the influence of behavioral control is primarily driven by consumers’ assessments of task difficulty and external conditions, rather than by value congruence. Emotional resonance stemming from alignment with brand values appears to be less relevant in this pathway.

5.2. Implications

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Theoretical implications

This study builds upon the DTPB by integrating the ECM and the ISCM to construct a comprehensive research framework aimed at uncovering the formation mechanisms of consumers’ continuance usage intention toward sustainable RTD beverage packaging. Furthermore, PS and PVF are introduced as moderating variables to examine their boundary conditions within the psychological mechanisms of green behavior. The findings not only confirm the applicability of DTPB in the context of green consumption but also contribute significant extensions and refinements to the existing theoretical system in the following aspects:

First, this study expands the extrapolative boundaries of the DTPB within the green consumption domain. Traditionally, the DTPB model has been primarily applied to contexts such as digital technologies and online services [11], with relatively limited explanatory power for sustained behaviors in green consumption. By introducing the DTPB framework into the domain of sustainable packaging consumption and systematically decomposing its structural variables into six antecedent dimensions—perceived usefulness, perceived enjoyment, external influence, interpersonal influence, self-efficacy, and facilitating conditions (PU, PE, EI, II, SE, FA)—this study achieves a more hierarchical and contextually relevant explanatory model. The results validate the mediating roles of satisfaction, subjective norms, and perceived behavioral control in continuance usage intention, thereby confirming the explanatory strength of the DTPB structure in green sustained behavior contexts. This enriches the applicable dimensions of the theory in environmental behavior research and enhances its ecological external validity.

This study elucidates the mechanisms through which perceived experience and emotional value influence green consumption decisions. Existing research on green consumption has largely focused on consumers’ rational considerations, such as environmental attitudes [16], cost–benefit analyses [18], and behavioral responsibility [17]. However, our findings demonstrate that PE, as a subjective emotional experience, significantly affects consumer satisfaction, thereby promoting continued usage intention. This insight suggests that green consumption is not solely cognitively driven but also involves substantial affective processes, aligning with the recent emphasis on experience-oriented perspectives in consumer research [58,59]. Accordingly, future green consumption theories should place greater emphasis on integrating affective factors, particularly in areas of design orientation, aesthetic preferences, and emotional value.

Moreover, this study clarifies the distinct influence pathways of different social impact sources within the social norms structure. By decomposing social influence into II and EI, the research reveals the multi-source formation paths of subjective norms. Unlike the traditional TPB model, which treats subjective norms as a unified construct, the findings show that the influence mechanisms of close relationships (e.g., family members, friends) and broader social systems (e.g., media, policies) differ and that both effects can be amplified through heightened perceived sustainability. This discovery not only supports the multi-level pathway view in social influence theory but also provides a theoretical foundation for the structured measurement of subjective norms, facilitating the evolution of TPB from a simplified structural model toward a cognitively nuanced framework.

This study also highlights the moderating role and significance of PS within behavioral pathways. As an individual’s subjective cognition of a product’s environmental attributes, PS was confirmed to significantly moderate multiple relational paths in this research, particularly those related to value perceptions and social norms. This finding introduces a new explanatory dimension to sustainable behavior research, emphasizing the subjective construction of sustainability meaning as a critical cognitive prerequisite influencing the transformation and persistence of green behaviors. Conversely, PS did not show significant moderating effects on certain affective paths (e.g., perceived enjoyment) or intrinsic control variables (e.g., self-efficacy), suggesting that its influence is context dependent. This provides a theoretical basis for future studies exploring the psychological mechanisms and boundary conditions of sustainability meaning construction.

Finally, the findings of this study reinforce the moderating role of brand–personal value congruence in sustaining consumer behavior. PVF was found to significantly strengthen the pathways from satisfaction and subjective norms to the intention of continued use, indicating that the psychological mechanism of value alignment between consumers and brands plays a critical role in the persistence of green behaviors. This finding extends the application of Consumer–Brand Congruence Theory in the context of green marketing, suggesting that when a brand’s sustainability values align with consumers’ intrinsic values, individuals are more likely to develop loyalty, commitment, and repeated behaviors—thereby generating a stronger driving force for the continuation of green practices. This mechanism provides empirical support for theories of value co-creation and identity resonance in green consumption.

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Practical implications

This study systematically identifies the key drivers influencing consumers’ continuance intention to use sustainable RTD beverage packaging from the consumer perspective, and verifies the moderating effects of perceived sustainability and value fit. These theoretical findings offer important practical implications for promoting sustainable packaging adoption. The following specific recommendations are proposed across four dimensions: business operations, marketing communication, product design, and policy guidance.

From the business perspective, optimizing the consumer experience is a crucial driver for enhancing satisfaction and usage intention. The research shows that PU and PE both significantly and positively affect consumer satisfaction, which in turn directly promotes continuance intention. Therefore, brands developing sustainable RTD packaging should integrate both functional utility and emotional experience. On the functional level, efforts could focus on improving packaging portability, insulation performance, and ease of recycling to strengthen consumers’ practical identification with the product. On the emotional level, packaging visual design, texture optimization, and participatory eco-friendly semantics (e.g., interactive elements such as “I am doing my part for the environment”) can be leveraged to stimulate consumers’ enjoyment and sense of involvement, thereby driving the emotional motivation behind green consumption behavior.

At the marketing level, it is essential to distinctly differentiate between interpersonal and external influences and strengthen social identity incentives. This study decomposes subjective norms into two dimensions: interpersonal influence and external influence, both of which significantly affect subjective norms and indirectly impact continuance intention. Accordingly, brands can approach social influence through two main channels: social communication and relational communication. Specifically, brands should enhance environmental-themed social media marketing and public opinion shaping by leveraging celebrity endorsements, KOLs, and eco-friendly challenges to create a socially legitimate environmental discourse and elevate public awareness. Concurrently, designing social mechanisms that encourage joint environmental actions with friends and family—such as eco-points leaderboards, referral rewards, and green challenge check-ins—can reinforce behavioral connections and perceived social pressure within close relationships.

On the product design and service front, increasing convenience and boosting user self-efficacy are crucial. The study indicates that SE and FA significantly influence consumers’ PBC, which in turn affects behavioral intentions. Therefore, improving ease of use and enhancing user confidence have practical importance. Businesses can promote standardized packaging systems with recognizable designs to help users quickly learn how to use and recycle packaging. At service touchpoints such as stores and platforms, a “guide–prompt–feedback” mechanism should be strengthened—for example, providing clear recycling instructions, training staff to explain sustainability features, and offering customers green feedback messages (e.g., your usage reduced carbon emissions by 0.05 kg this time)—to enhance consumers’ sense of control and participation in environmental protection.

Finally, at the policy and institutional level, efforts should focus on strengthening the communication of perceived sustainability and guiding value co-creation. This study demonstrates the significant moderating effects of PS and PVF, indicating that consumers care not only about whether packaging is environmentally friendly but also about its alignment with their personal values and social identity. Therefore, governments and policymakers should act at the macro institutional and cultural advocacy levels. First, governments should actively promote the establishment and implementation of eco-label certification systems for sustainable packaging products, facilitating the widespread adoption of standardized and authoritative labeling frameworks. This will make it easier for consumers to recognize environmentally friendly products, thereby effectively enhancing their PS. Second, public campaigns, educational programs, and themed initiatives such as green cities and plastic-free days should be utilized to cultivate public awareness of environmental values and consumer responsibility, integrating green consumption into broader public culture and urban image building. Lastly, governments should encourage enterprises to engage in value co-creation and collaborative public agenda setting. Through a tripartite collaboration among government, enterprises, and the public, environmentally friendly packaging can be positioned as a medium through which consumers identify with brands and express their value attitudes. This approach achieves a dual effect by combining institutional regulation with emotional identification.

6. Limitations and Future Research Directions

First, the cross-sectional survey design employed in this study limits the rigor of causal inference. Although the structural equation model, grounded in a theoretical framework, supports most hypotheses, it cannot fully rule out potential reverse causality or confounding effects from third variables. Future research should adopt longitudinal designs or experimental methods to dynamically track changes in consumer behavior and verify the causal effects of the proposed model. Second, the sample was primarily drawn from a specific region or consumer segment, which may impose limitations due to regional cultural differences or consumption habits, thus affecting the generalizability of the findings. Notably, consumers’ perceptions of sustainable packaging and value congruence may vary significantly across countries and cultural contexts. Future studies should broaden the sample scope to enable cross-cultural comparisons. Third, although this study refined the moderating roles of PVF and PS, some moderation hypotheses were not supported, suggesting that the mechanisms of these variables may be more complex. Future research could incorporate additional psychological constructs (e.g., environmental responsibility, green trust) or contextual factors (e.g., economic incentives, policy environment) to further explore their influence pathways. Moreover, the variables used in this research were mainly based on self-reported questionnaires, which are inevitably subject to social desirability bias and recall bias. To enhance measurement objectivity and accuracy, future studies could integrate behavioral tracking data, neuroscience techniques, or other multimethod approaches. Lastly, as the data in this study were collected through self-reported questionnaires, potential biases such as social desirability bias and recall bias may have affected the objectivity and accuracy of the responses. These biases could result in the overestimation or underestimation of certain behaviors or attitudes, thereby influencing the robustness of the findings. Future research could mitigate such biases by triangulating self-reported measures with objective behavioral data, observational methods, or experimental approaches. In addition, improving questionnaire design—such as incorporating reverse-coded items or shorter recall periods—may help enhance response accuracy. Longitudinal or mixed-method designs could also provide a more comprehensive understanding of the constructs examined.