I'm sure everyone has seen them all over town, in cassiopea hollow, in trains of 15 characters on follow, etc... and yes, they have a drastic effect on the economy, and no matter how much they try to ban them, they just keep coming back.
Ok, here is a crazy idea. Instead of fighting RMT, we should join them, and make everyone able to sell gil or their character. Think of it when mp3 pirating was happening, with futile attempts to sue downloaders by music companies going bankrupt. Then itunes came out and now almost everybody is downloading it, paying for it, and apple making a ton of money.
If SE made like an official game item auction site, where everyone can put their gil, character, or rare item for sale, it would pretty much devalue these RMT people and allows people to play and make money in the process. That will motivate people to actually hop in the game and make items to sell in the wards to make money for real life. Think about all the people who are jobless now, but could really use that rent money, or want to buy a better pc. Maybe instead of paying with money to buy something, they can use crysta, and play for free that way. Just think how many subscribers SE will get. Crazy idea or the craziest idea?