Like, I just was thinking about how lots of pet species will just eat as much food as you give them to the point of making themselves sick, and keeping them at a healthy weight requires not giving them access to too much food. Obviously some humans have problems with this, but imagine how bad things would be if everyone were basically psychologically incapable of not eating food when we had access to it even when we’d had enough, given our dramatically higher access to food due to agriculture.
This would probably have prevented civilization from forming, can’t have specialized labor if the ones making the food will eat as much as they can and die, every time without fail. Society stuck in hunter gatherer mode