What? This is retarded.
First off, let me just point out that myself along with plenty of other people have been scammed in the past with no retribution or consolidation at all. It would almost be a slap in the face, and not to mention down right irresponsible, to allow people to "Take matters into their own hands". If someone kills your friend, I'll bet you'll want to avenge them right? But it still doesn't make it right. If someone steals from your friend, you might want to steal something in return. Doesn't make it right.
If you sell an account and the person charges back, sure, recover the account. Who wouldn't? As long as you have all the evidence of the charge back what's anyone going to say?
If you're being an idiot and buying gold and someone takes your paypal, well tough luck. Get them banned and get over it.
If everyone would just take a minute to properly educate themselves on trading precautions and safety, all of this can be avoided. Don't tell me it's not possible either because it most obviously is.