The international market for luxury goods puts pressure on many wildlife species, with potentially irreversible consequences for many of them. Although classical economic theory suggests that trade alone would not drive a rare species to extinction, in practice numerous species are being threatened by overexploitation. This is for example the case for sturgeons, exploited for their caviar, of which all 27 species are threatened with extinction. We performed a caviar-tasting experiment, combined with a modeling approach merging ecological theory and psychosociology. This allowed us to demonstrate that the human predisposition to place exaggerated value on rarity drives sturgeons' overexploitation, despite caviar's ever-increasing price and the imminent loss of these species. These findings suggest that this mechanism probably drives the entire market for wildlife based luxury goods.