I've no idea how they convince themselves they're going to get away with this sort of shit.
If that is their thing, I'm sure they could find any number of people willing to play around with consensual non consent instead of destroying someone.
In the early 2000s and before it without the social media as it is now you were very disconnected. This means that perpetrators could easily hide and you couldn't contact other victims. Also feminism wasn't as integrated into society as it is now.
I'm certainly no expert and a self admitted dumbass but I always assumed it was something along the lines of these people get rich and famous, get used to being able to get whatever they want, anytime they want it. Everyone around them tells them they're the shit. Girls (or guys) are falling all over them. But then they find the one thing they want but can't have... And then they kinda just have to have it cause they get everything they want, why would this be any different. So they take it.