Rez.They don't just mysteriously vanish off the face of the earth or anything. Seriously...name me a game from the current generation that you flat out CANNOT find for less than it cost new. I can't even thing of one. If we're talking 3-5 year old PSX, sure....but if you waited that long, you missed the G-spot for buying cheap.
Hell I don't pay $50 for new games now anyways, so the price increase isn't really going to affect me