At $500 I'd hardly consider the PS3 a huge theft risk, considering the whole verified CC thing, which would just mean you sold one more PS3 at the end of the week if nobody returned it. Hardly a loss for a game store or a video store.
The store that I worked at made crazy money renting and selling 360's & PS3's, and the type of folks who would try to steal them never had a CC with that kind of room on it in the first place. In the end, I would say it's far dumber NOT to rent them out, considering you could rent out a bunch of $60 games that could easily lose you as much due to theft.
But, I'm derailing the shit out of this thread, so I'll leave it at that.