Why not have a rule that you have to make 6 or 7 posts before you can make a post with a URL in it to the Free MMORPG Section?
And when it displays "Hey you have to make 6 or 7 posts before you post here" it could add "if this is a browser-based game, please post this in the browser game section"
This would also cutdown on the gold seller posting.
They can also just combine both....in order to make a thread you need 5-10 posts and once your able to post ull need to insert w.e numbers or words are displayed in the CAPTCHA......that will prevent spam bots for sure