It took a while to figure out, but I was sure there was something that was not "right" about contacting losing bidders.

Ebay is providing an auction service as a commercial enterprise in order to make money. They provide the means for sellers and buyers to come to terms. The seller (and buyer) recognize the value of the service and are willing to pay for it. Ebay or any auctioneer incurs expenses in conducting the auction. When someone uses the information provided by the auctioneer to their own profit, and cuts out the auctioneer, that is not right.

If you have the additional chips for sale, I believe the right thing would be to put them up for auction.