From my many experiences, I would say that the average joe is not the most likely. Instead, it's the alpha males/females of society, who, since school days always picked on the average joe's and jane's. They were always bigger, more aggressive, and meaner. As adults, little changes, except for jail house degrees of doing it better, added to their bullying experience. That, and a lot of hostile experience, would be the formal training, maybe some boxing also, that they possess. They learned early on force was productive for them.