[Fred]

I can recall this happening on ebay, but never an AH.

If it were an AH and the offer came a day or two after the auction, then I'd be wondering "what's up with this"? If it occurred a few weeks after the auction, then I'd be thinking the winning bidder reneged on the bid.

I've contacted a top AH (not one of the little guys) before and inquired about an item that didn't sell and it was made available for 30% less the minimum bid (no other fees, besides shipping attached). I was happy to pick it up.

It's probably up to the discretion of the AH to sell unbid lots and I'm pretty sure the AH would have to get the consignors permission or sell it for the cost of the item sans the seller's premium charged by the AH.