That's one of the things that make this game awesome. Consequences of your choices.
But I have to say that the MC is really bad at putting things together. Ridiculously so. Somehow, he hasn't figured out the prostitution ring despite knowing what Quinn's doing. He hasn't even figured out that Quinn is selling drugs, how he possibly could have missed that. I think it's in Episode 7 or 8 that he thinks about how he can't put the pieces together. He's the worst detective in the history of games.
I get that it's necessary to dumb him down for the sake of the story development or he would have told Sage and Maya about it and that would have been really hard to write such a huge split in the story. Personally, I would have had him figure things out as the game progressed but also given him a reason to be quiet about it, like that someone warns him how dangerous it could be for his friends if he told anybody. But now, he's practically clueless.
But what if the MC knows, he's always known, he's always seen and heard, but he doesn't care to mention it or try to moralize it, since he uses what she offers, prostitutes and weed.
Imagine the scene where he sees Quinn with the drug, getting it or selling it, Quinn looks at him not knowing what to say to him, and he just acts like he doesn't care, she tried to hide it from him, but he always knew.
I know the MC is gullible, but there has to be a limit, it's impossible for him not to know.