'Catching' RMT only in batches is part of the problem imho. How often do they do it? Every one month? Never really counted the interavals but it's enough time for the RMTs to amass gil, get those gil sold, and have those gil buyers spend money on legit items on the market. SE can remove the rmt and punish the gil buyers periodically but they can't remove tainted money once it goes past that. Remember the first few months after launch? Apparently legit crafters getting their gil taken away because their items were bought by gil buyers and the outrage in the forums and all that? Remember that guy who even wrote a non digital letter and really mailed it to Japan? Where's that now? The fact that it's not happening probably means that offenders get removed but already laundered money does not.

Like really, if I were the boss of these RMTs and realized that a company is only rounding up my goons one day of every month and they can run amok the rest of the month, my next thought would be, would I still make profit if I have to rebuy accounts for my soldiers every month? Looks like the answer is yes.