Another Question for Evolutionary Psychology

Evolutionary psychologists argue that human behaviour can be understood as an unconscious attempt to maximize inclusive fitness. "Wait a minute," say critics, "doesn't this lead to the prediction that men will pay substantial amounts of money to have their sperm deposited in sperm banks?" "No," say evolutionary psychologists, "you have to look at what behaviour maximized inclusive fitness in the Envioronment of Evolutionary Adaptedness (to simplify a bit: the African savanna during the stone age), and they didn't have sperm banks back then. What's more, some behaviour that was beneficial in the EEA but is detrimental now is still exhibited by modern humans."

A popular example of the latter goes as follows: In EEA-type environments "fat, salt, and sugar are in such short supply that when they are encountered, the useful response is to consume them. Fat provides twice as many calories per gram as carbohydrates. Sugar is often associated with ripe fruits, and seeking it out was usually beneficial. Now that we can choose our foods, we prefer what was in short supply on the African savanna." In affluent modern societies this leads to weight control problems.

But to be a little more precise, this line of reasoning leads to the following hypothesis:

In modern affluent societies the vast majority of people is morbidly obese.

Empirically, this is not the case. Why?

(An earlier question for evolutionary psychology)