Environmentally friendly consumables and products are often perceived as superior to their conventional counterparts. The reason for this, at least in part, is that people tend to glorify eco-labeled objects. For example, people prefer the taste of coffee called “eco-friendly” in comparison with another cup of coffee called “conventional”, even when the two cups of coffee are actually identical and merely named differently. What is the underlying mechanism of this eco-label effect? Do people report superior evaluations of eco-labeled products for intrinsic reasons or because they think this attitude is approved by others (a social desirability mechanism)? In two experiments, the participants’ concerns with social desirability were manipulated by telling them that their taste judgments of consumables were monitored by others. The eco-label effect was just as strong in the high social desirability concerns condition as in a control condition (Experiments 1 and 2). However, the eco-label effect was stronger in magnitude for participants who were told that consumers are morally responsible for the environmental consequences of their consumer behavior (Experiment 2). Taken together, the eco-label effect appears to be caused by intrinsic desirability processes, not by social desirability processes.