Well, after having returned 4 defective Vizio tv's to costco for replacement (since Thanksgiving) and recieving an "A grade" replacement directly from Vizio that won't recieve sound correctly on the SD channels and has a noticeable ghost image on all inputs, I'm waiting for a better tv to come to Costco at a good price and then I fully intend to return what I've got now and upgrade.
Not everyone who upgrades their tv's there is abusing the policy and ruining it for the rest of us. IME, anyone who returned a Vizio probably had a legitimate reason to return it. If they profited from that, then more power to them. You should probably ask people why they took advantage of Costco's policy before you condemn them for doing so.
Jack