Look, if you're a developer and not a moron, you really don't want a secondary market around your goods. They can be used for gambling, money laundering, and all number of illegal activities. Plus, you make the market for your virtual goods more efficient, and more efficient means less profitable.
CIG's solution in this case, if what is alleged here is indeed their dolution, shows how corrupt they are. In this case, they should have pointed to the ToS and nuked the account. End of story.