The success of eco-labelling is due to the combination of two main factors: on the one hand, the interactions between the private or public nature of environmental attributes (i.e. the type of individual or collective benefits they provide) and on the other hand the number of consumers with selfish or altruistic social behaviour. This second factor, particularly, helps understand why some eco-labels applied to the same type of products and with a fixed level of private and public attributes work differently according to the country. We show that if some consumers’ altruism level is high, their purchasing behaviour may prevent more “selfish” consumers from having access to the eco-labelled good, and therefore, reduce the desired global environmental benefit. Moreover, it seems important to avoid a uniform policy by setting up marketing strategies adapted to different segments of consumers.