I've noticed from both ArenaNet and players that they assume if they sell gold in a controlled market they are able to stop illegal RMT. I don't see how that is possible, considering all the RMT traders have to do is make it more profitable to buy from their website than ingame.
As expected, you where able to buy gems and trade them for gold or other items; that's not a problem at all to me. Guild Wars has always been completely cosmetic, there's nothing to gain other than looks when it comes to gold.
But to say they're doing it to control the RMT market from illegal activities is an excuse.
I have played free to play games before, it has never stopped bots or RMT. It has always been more bang for your buck to buy from the illegal traders than to buy from the company.