Its not that they closed it off its how they did. Imagine the first group who figured that out its a genuine strategy that out smarted the game designers that should be rewarded in video games. But at the same time it has become an exploit so it does need to be dealt with but there is a right and wrong way to do that. The wrong way kills the euphoria by cutting you off in a silly way. If it looks like you can go somewhere than you should be able to.