Golly - gee -- I'm amazed lately at how some innocent questions can turn ugly!!!!!!!
If you want to use them, fine, use them, if you don't then, fine, don't. Who can really tell the difference anyways! If I find cheaper, i use them. I bought 2 king size the other day at a thrift store...$10.00 total. Can't beat the price. I use them for testing new designs on my longarm. My problem with the used ones........there were stains on them that I'd really rather not try to figure out what they are........oh, maybe some ate pizza in bed....I sure hope that was it!!!!