The money? Please. The cost of running a forum is a trifle compared to what they're going to be spending for server farms and bandwidth.

I agree with the decision, really. "Official" forums always devolve into a seething mass of asshats that (usually) mis-represent the community and put off potential new players. Best to dilute the negativity a bit. It only takes a small percentage of a forum's population to make the whole place unsavory, and the more these few disgruntled players (if they even are players and not just haters) get spread out, the better it is for the game.