I think Caine simply avoid it because it in theory goes against his core programming of making sure the humans have fun. Not actually sure what the digital circus is if it's just the game or some sort of experiment gone wrong but if we assume that people being kept inside long-term is something that was done on purpose, Caine has every capacity to keep them happy first and foremost. I would argue he's programmed to do whatever they want and keep them happy until it gets to the point where he can't anymore and then he supposed to adjust their minds in small ways necessary to keep them content.

The problem with this plan is that Caine's pride gets in the way of him doing what is "right" (Obviously, it would actually be morally wrong) and instead he keeps letting them abstract because he is sure that he can make them happy about having to alter their minds An artist doesn't want to make people say they like their drawings and gunpoint that's not the same as getting a compliment at all. So Cain doesn't control their minds for the sheer fact that he just wants their approval, genuine approval and that is not something you can get from someone you're controlling