I did some harvesting at most of the strip casino's and the only one i had problems with was at the Luxor. They got hung up when I asked at the cage for some chips since "I collect them". They said their policy is not to sell chips to collectors (could have just been a group of casino cashiers that were in a bad mood that day). So, my advise is not to mention you collect them when asking about chips at Luxor. All the other places were very nice and many even went and searched out for uncirculated ones in their cage.