That's why you wait until after the second playthrough. Supposedly, every quest you haven't completed up to then gets scaled to 49-50.
They only scale up like this after you beat TVHM. So you have to save sidequests for the end of that playthrough for them to scale to level 50 difficulty and rewards. Yet, you really still have to do some of them as you plod along, or else the story missions will greatly out-level you. There are a few guides on which ones you should save if you want some good rewards.
Playing: All games on hold for Borderlands 2 PSN ID: Call_Me_Queequeg