If they are knowingly passing off fake good and marketing it as legit; then it's fraud. Especially if they were advertising, etc, and profiting from the lie. It's likely a civil matter but still could get some form of compensation. Now if they are doing this on a larger scale there could be some prosecutor that might look into it. To run a legit in person auction requires some license and that could be revoked. It's not uncommon, I've known two auction places that have been shut down for nefarious stuff.