Among Generation Z consumers, dupe product consumption has rapidly diffused through SNS-based online word-of-mouth, evolving beyond a simple price-substitution choice into a distinctive form of generational consumption culture. Nevertheless, extant research has predominantly conceptualized dupe consumption as an extension of rational consumption tendencies, such as value-for-money considerations or price sensitivity. Addressing this gap, the present study reconceptualizes dupe product consumption not merely as a rational choice, but as a phenomenon shaped by consumers’ psychological motivations and the broader socio-cultural context in which these choices are embedded. To this end, a stimulus-based survey was conducted with 187 adult Generation Z consumers. The findings reveal that perceived coolness of dupe products exerts positive direct effects on online word-of-mouth intention, product evaluation, and purchase intention. More importantly, self–brand connection emerges as a central psychological mechanism through which perceived coolness is translated into behavioral responses. Furthermore, consumers’ value consciousness moderates the strength of this mediating process.