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.
Animals that overeat are completely in control of their actions, they just don’t see how eating makes them sick. Humans on the other hand are completely aware of this and yet we still can’t stop eating.