The easy answer is, they don't care.
Maya fans won't like Quinn, because Quinn's behavior to Maya is inexcusable. Unlike Sage who misunderstands the situation as Maya not knowing Quinn's humor/style, we as the semi-omniscient audience know that Quinn is fucking with Maya without any concern for the damage she does.
Quinn fans simply don't care about Maya, and consider she is responsible for her own choices and behavior, and if she was naive enough to think all she had to do was pass the initiation and she'd get free tuition (which was her understanding), then she deserves all the shit that comes her way. I even have a bridge she might be interested in buying.
Then there are those (like myself) who enjoy all the characters for their merits and don't really concern myself with their short comings unless I find them too annoying. Quinn isn't annoying me, plus she's a very interesting character to pursue. In real life? Fuck no! But this is a no-consequences endeavor (it's just a game), and I want to ride Quinn out to see where it goes.