Consumer behavior in sustainable development is one means of action to reduce human impact upon the planet. In this paper, we are interested in the effect of fashion on environmentally friendly consumption. We have worked on an impure public goods model, with two goods generating both private and public characteristics. This model is distinct from other existing impure good models because goods also generate a 'social' characteristic depending on which good is fashionable. We study how demand for environment quality depends on the fashion effect. The comparative static result underlines certain noteworthy results on environmental demand. This depends on which good is the more fashionable. Green good attractiveness can snowball environmental demand whenever standard good attractiveness might interfere with environmental motivation and curb environmental demand. A numerical application is used to resolve consumer maximization programs. Using data from a survey on eco-labeled seafood, we estimated the level of standard fish versus eco-labeled fish consumed when a fashion effect influences choice.