It may depend on who is handling the situation, the admins could be more liberal in handing out bans for suspected links between accounts than regular mods. Theymos may also not be privy of the situation.
For what it's worth Korner has long been autobanned along with a huge number of his alt accounts, the issue is they push out more new troll accounts each time.
The mods would be at a loss between allowing free speech or following their hunch and shutting dowm such potential alt accounts who share habits with a previously banned account. To me it's a clear case of evasions, but I'm not the one burdened with carrying out the action.

Self mod threads is encouraged as it is used to prevent spam, putting a price on it would be counter productive. A rank up criteria could work theoretically, with jr member as the minimum threshold. it would be abused to a extent, but can reduce the rate of new trolls.