Did Gar255 put a gun to his head? No one forced the bidders to do anything.

Having an alt that artificially raises the bid price is similar to a secret reserve price in an auction. There's nothing inherently wrong with it except that Garr255 should have warned bidders that he might do it. I rank his actions there as "a bit shady," though he handled the fallout badly (due to inexperience, I suppose).

In any case, alts aren't against forum rules, and scammer tags are typically only given when an explicit agreement is broken. Garr255 never promised not to bid on his own auctions. He never even promised to honor the results of the auctions. Without contracts that say otherwise, auctions are only devices to assist in price negotiations.