are you really all pretending like account trading/selling has been non-existant in other places ? how is that even a concern here?
characters/accounts are changing hands on every server. If i wanted to buy a character on any server, i could easily go and get it. A character auction system doesnt change a damn thing. If they created instant 60 characters for you on sale ... yeah that would be a turn off. But buying characters from people who level'd and played them legitimately is nothing game-breaking, it's not like a new level 60 character appears out of nowhere.
And again, whether they officially allow it or not, account trading will happen anyway! if not over this website, it will happen via other websites.