I mean, look. I know nobody wants to be the person who throws a user off a site, and nobody wants to think there might be fishy stuff going on their site either. Their first line of defense was to tell me there was no way I could know if this user didn't actually make a purchase, and I'm thinking: if you LITERALLY look at who wins, it's not that guy. But, I stayed polite in my reply and just said that I was committed to breed preservation, and it would be a shame if confidence in bidding was undermined by certain user behavior.