How fair is this?

I just noticed a interesting auction. The seller states that his item is listed on both Audiogon and Ebay. And which ever site gets the highest bid, wins. Maybe its just me, but I am hoping he gets no bids on either site.
Seandtaylor99, ever here of a contract????

An offer to sell at a certain price and an offer to buy at a certain price constitutes a contract in the most simple of terms.

Can anyone really imagine going to any auction anywhere, being the winning bidder and having the auctioneer say, oh sorry, we decided to sell it to someone else.

Don't be stupid.
Fairly obvious, this is a bad precedent. It is most likely that the seller will be in violation to previously agreed upon rules and regulations of at least one host auctioneer's web site. As such, the seller is in all likelyhood not a person of his word, and can not be trusted. I discourage everyone from enabling this practice.
Pawlowski6132, the seller did highlight his tactics. There's nothing underhanded here, as it's clearly stated that the higher bid of the two sites wins.

If you don't like it then don't bid. Jeez it's only a piece of hifi equipment !
What seems even worse about this. On ebay it ends in a couple days, ends today here. On ebay it is a buy it now price. No reserve auction here. So if you win it here for less then the buy it now price on ebay, you have to wait 2 days to see if he has a better offer there. And he doesn't state anything on ebay about being listed on audiogon also. To me, this is bad business.
Someone ought to e-mail this thread to the seller, assuming he's not watching this thread, to give him a heads up. I'm curious if he would make a post of explanation. A penny for your thoughts double auctioneer.