I would agree too, at least for pro users should be a way to hide everything that lets a possible contracting party/publisher see in the first place, with what a game is made.
Unfortunately there is a lot of disregard concerning gamemaker packages like gamestudio, darkbasic, 3drad, torque and so on in the whole scene.
So as a game developer you are in a much better position to negotiate, if a possbile partner just see's your game at first hand, without having in mind 'it's clicked together' with the same engine that he get's 10 bad entries to review a year...