If they're doing a good job of it more or less the way you'd be doing it, bail. You want to be crusading for your future users, saving them from the crap they would have to put up with if you weren't helping them. If you don't think you are making a big difference for your users, you won't have the necessarily inner fire to win.
Ideally you do a startup where other companies are doing something badly, their users hate them, and they still make money.
Ideally you do a startup where other companies are doing something badly, their users hate them, and they still make money.