In case you're wondering, this happens fairly regularly, and not only with drop cloths. People use all sorts of things and then return them, I mean, why would they want to clutter up their house with things they're most likely never, ever going to use again? And, of course, the corporate side of retail is looking at the big picture. If you treat a customer right, he might spend up to $80,000 in his lifetime at your store - so why dick around with $80 in drop cloths. They don't think about how much you're enabling bad ethics. I mean, what are ethics when compared to possibly earning... maybe as much as $80,000 in retail sales?
Anyway, this has been my bitch of the day. Why buy something when you can rent it for free, use it once and get your money back.