This simply isn't true. They're just very careful about protecting paying customers, and it's very difficult to separate spam-bots from paying customers in an automated way. It has to be automated, because like spam email, the volume is simply too high when pitting hundreds, thousands, or perhaps tens of thousands of dedicated RMTers against the finite resources available to NCSoft. And when it comes down to do the GMs spend their time helping players out with bugs, being stuck, corrupted characters, etc. or spending their time deleting "asdfasdfa" and "fdsdfs"...I'd rather they didn't.
World of Warcraft does a fine job. You get spammers occasionally but its a quick right click and they are out of your hair. Botters are banned very quickly as well. All of this without an impact on the game.
It's a cop-out to say there's nothing that can be done. Blizzard and SOE have done a fine job, NCSoft has been a joke in that regard. They aren't "protecting paying customers" at all.
You protect your paying customers by preventing them from being scammed. NCSoft doesn't do that.