The games on demand pricing has to be that way though. If Games on Demand cost literally half the price Gamestop charged, the retailers would revolt, which would cause the publishers to revolt.
The only reason Valve has the power to charge what they charge is because they incrementally built that power - retailers at one point threatened to pull games from shelves for using Steam's authentication!
There's also a difference between Valve and Microsoft (or any other "platform" owners) that they still have to deal with retailers to push distribution of the console itself...
The only reason Valve has the power to charge what they charge is because they incrementally built that power - retailers at one point threatened to pull games from shelves for using Steam's authentication!