There's a difference between fantasizing about something and really doing it. If I responded to some people here (not you) like I've fantasized about doing sometimes, I'd have been banned a long time ago. In real life, I've imagined scenarios of things I'd do at XYZ place. Not doing anything else that breaks the law, but speaking my mind on things that are better left unsaid or taking actions that are better left untaken. But I don't do them. Because after I got it out of my system in my mind, I think, "Okay. But what am I really going to do? What am I really going to say?"
It's okay to have wild, crazy thoughts. It's not okay to do them for real. In a holodeck, it's all "let's pretend!" You'll note that Tendi didn't want to go along with it anymore after a certain point and Mariner came to her senses by the end of the episode.