Except that it does suggest that mistreating people is fun for at least some people.
Killing people in a computer game is fun for many people.
Without empathy, anything you do with other people is pretty much a game. Finding a way to abuse a person without being punished for it, is like solving a puzzle. One could move to more horrible acts simply as a matter of curiosity; just like a person who completed a puzzle wants to try a more difficult puzzle.
(By the way, this discussion partially assumes that psychopaths are exactly like neurotypical people, just minus the empathy. Which may be wrong. Which may make some of our conclusions wrong.)
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.