Fear, I might would agree if it was particularly difficult to pinpoint people who blatantly rig the pots, but it's not hard at all. Moderating it is as easy as watching a replay and glancing at the transaction history of the accounts involved. This should be a commonsense rule, both to follow and enforce. Why should this sort of blatant absence of respect for the Toribash community be allowed to subsist? The only people who would defend the rules the way they are now, are the same people who benefit from there not being any moderation on this in the first damn place.
And I'm not one much for conspiracy theories, but two of the times I've witnessed a decap prize get rigged, a moderator/admin got handsomely rewarded out of the earned TC. This sort of comradery between those who rig and those who enforce rules should be investigated; short of doing that, at least close the loophole that is allowing for this to occur.
This sort of issue is only going to grow in attention now that the admins have publicly announced it as a legit course of action. Fear, your argument that you should only have decap prizes on a private server is irrelevant as well. It would not be hard for those who rig the prizes to both decapitate and disqualify in the same turn. There is nothing short of an intervention from a GM or admin that is going to stop this problem.
I can only hope more people show up to support this effort as well.