I think not everyone is built for empathy. Or at least not in every situation. Some are so consumed by their bitterness, or hatred, that causing pain is actually what they hope for. Knowing it's going to hurt fuels them because they have justified it.
In that case, maybe the idea of right and wrong, and rules and religion has its place.
Sadly I think you are right @kaerpediem. Thank you very much for the support.