I must admit I also do not always rescan every exact chip I put up for auction. When you're selling uncirculated LEs or new house chips, the only difference someone might find is the rotation of the inserts. But when a chip is unique or worn, you'd better be selling an equal or better chip, or you're committing fraud. If I can see a difference between the chip I'm selling and the one I scanned, I always rescan. More importantly, I answer my email. Selling on eBay implies a willingness to communicate via email. Period. Your email address is the only identification provided.

You hit the nail on the head. More important than any specific detail on any specific auction, the question is whether a seller is acting in an ethical manner.