I remember when Kingdoms of Amalur: Reckoning had just been released, and the fans were concerned that 38 Studios was focusing on the DLC for that game when they should have been spending their time fixing bugs and balance issues. The studio's explanation was that they were contractually obligated to get the DLC out on a certain date. I would imagine that to be the case here as well. It's not that Volition wants to prioritize the DLC; it's that they have to. The business of business is business.