From sustainable consumption to green purchasing: The mediating effect of green brand value and the moderating effect of green customer citizenship

In today's marketing ecosystem, environmental sustainability practices play a critical role in brands gaining a competitive advantage, yet an "attitude-behavior gap" persists where environmental awareness does not always translate into green purchases. This paper aims to explore the effect of environmental sustainability practices on green product purchasing behavior with the regulatory role of green customer citizenship and the mediating role of green brand value. Data were collected from 1236 participants in Kocaeli, Turkey, using a non-probability convenience sampling method via an online survey. The reliability coefficients of the scales ranged between 0.72 and 0.90, supporting the structural reliability and validity of the research. The structural findings confirm that environmental sustainability consumption behaviors positively and significantly affect green product purchasing behavior (H1) and green brand value (H2), while green brand value directly promotes green product purchasing behavior (H3). Crucially, testing the theoretical model reveals that green brand value mediates the relationship between sustainable consumption and purchasing behavior (H4), while green customer citizenship moderates this indirect effect (H5) by significantly strengthening the relationship at higher levels of citizenship awareness. Demographic factors including age, marital status, education, and gender were included as the control variables of the analysis. These results demonstrate that sustainable consumption translates into actual sales through cognitive and emotional mechanisms, offering retail managers actionable guidance to foster green customer citizenship programs and build transparent brand equity.