They do, but if I had a successful DD service and a publisher said to me "We want to use your toolset in our game, and we want you to make that game available for download indefinitely for customers who buy our game from our retail partners. We also want you to make the game available for download, using your company's bandwidth, if customers decide to install it using the CD key and not from disc. However, we won't allow you to sell our game, we expect you to provide this service to us effectively free, minus the Steamworks licensing costs (which probably won't be much compared to the profits if a game was sold through Steam)". I understand your point and why Valve have to accept it, but I wouldn't be pleased about it if it was me. I'd be looking at ways to negotiate so that Steam can sell the games - there seems no reason that can't happen besides the Game Group being greedy.