Chimpanzee behaviour is chimpanzee behaviour.

Aspects of that behaviour appear in the behaviour of other primates, but not all primate groups have identical behaviours.

Chimpanzee behaviours also vary by troop and circumstances, just as might be expected from social behaviours.

Such behaviours _exist_, but they may not in fact be optimal, inevitable, etc.

Perhaps chimpanzees behave as they do 'cause the bonobo's didn't invite them to the cool parties.