Exactly. That's why we shouldn't create situations which provide incentive for [thing_you_don't_want_to_happen].

I'm sure this has been covered before, but why does the forum even allow sig ads? The forum profits from them indirectly at best, and possibly loses money on [official] forum ads that theymos auctions. Seems ...counterintuitive? You agree that it's the main incentive for account farms & account dealing, what would be the drawback of banning them?
I know I'm opening another can of worms, but.