I think he did it to avoid confusion. If you open an auction, you should stick to it. Example ~ if I bid $10 through the auction thread, my bid stands. If another person offers you $20 through your other thread, then what happens?
I get disappointed because the chances are high that you happen to take the offer in your other thread over the bid I made in your auction thread. It basically means that it's pointless to have an auction thread open.
I can definitely understand why he deleted the threads even though it wasn't against the rules.
If I get $10 bid and someone offer me 20$ then I would ask him to place bid on auction.Confusion is when someone wins auction while on another sale topic someone offers to buy at listing price but here this isn't a case because sale topic was listed with price,just asking for offers.
That is why your post is deleted if you offer the domain for sale for $10 then stick to it and don't ask them to post a bid in your auction thread. If that happens to me I would be disappointed as I am looking to pay for a $10 domain but I will be asked to post on another thread to because someone just offered a higher price. Not everyone likes to join auctions.