Is it actually very common for people to have violent sadistic fantasies, possibly involving actual people in their lives?

I just kind of wonder with how casually people express these thoughts. It's a little disturbing how normalized it is to entertain such notions, given how other types of fantasies are very stigmatized.

Like when discussing char.ai, acting out sexual or romantic fantasies is something a lot of people do, but it's considered embarrassing. While people freely discuss violent roleplays without any shame.

And then there's the cliche of fantasizing about killing one's boss or coworkers.

Are these really common thoughts for mentally sound people to have?