Well, what would happen if a flaming cheese meteor landed on the chip?

Katie, this is not a "live" auction, this is an online auction. There's a fundamental difference between the two, and it's unfair to bring the rules from one auction venue over into another.

To answer your inappropriate hypothetical question, yes, he may be able to shout out "I change my mind", in some cases. He may be able to bid on his own item (shill)in some cases. He also could have a case against the professional auctioneer who failed to provide proper fiduciary advice.

The fact is that ending an eBay auction early by first canceling all bids is not only allowable, it's actually suggested by eBay, in part because of the fundamental differences between online and traditional auction venues.