So you're going to pay someone to sit there waiting for a 30 second window in which some random compromised account logs in? That just doesn't make sense. Even at Chinese farmer rates.
Why pay somebody to sit in front of a computer? It can all be automated. The receiving program automatically logs in, and then pages, messages, whatever, the person to come clean out the account. Also, there are bots to automatically clear out guild banks, sell things, etc. I don't think that the thieves consider themselves bound by Blizzards ToS. This just makes their lives a bit more difficult, but nobody said gold selling was easy.