You know what, to put it bluntly:
"WoW rips are not allowed because we said so, if you don't like it, gtfo."
Finally a good reason. This reason is valid, and non-hypocritical. If everyone would just admit that the above is the reason for the rule, and drop all their imaginary moral and legal pretenses, all of these arguments would cease.
You've yet to establish that gold selling is immoral at all. WoW model ripping though has been established as immoral. Hence your argument fails.
You've yet to establish why model ripping is any more immoral than gold selling. Hence your arguments have been failing for a while.
The WoW people have made it clear that while they do not specifically endorse WoW model rips, they're definitely okay with it, and are interested in seeing what is done with them, because they think it is cool. If the owner is okay with you using his property in some way, then there is nothing immoral about using it in that particular way.
Gold Selling both breaks a contract, and is exploiting someone else's property for profit - when you explicitly don't have the right to do so. It's kindof like if someone goes and borrows your lawnmower then rents it to their friends for money. They have no right to do so, even if they have the right to use the lawnmower due to your permission.
I whole heartedly agree with elenai and ht, and there are lots of good reasons to keep wow model rips off the site, plus they have the right to do so (keep WoW models off the site) - but your morality argument is fail, and the force of it's fail has been the driving force of this thread for months.
If everyone had taken the stance Elenai and HT just backed from the beginning, this thread would not have needed to pass one page. On the plus side though, checking this and seeing the funny crap people have posted has brightened my day many times.