There were strong and weak, decided by time and place. The strong stepped on the weak, whenever they got a chance.
People were strong in groups, groups with sufficient numbers. The weakest were those who were alone.
When someone strong stepped on a weakling, he/she couldn’t fight back. Other strong people found it offensive. No, it’s not the strong who stepped on the weak that offended them. But it’s the weak who offended them. So they also stepped on him/her. Their weakness was offensive, because that was the easier choice.