Lets say they got the C&C games. They could have a C&C collection that included "newer" C&C games like Red Alert 2 but also the original Red Alert (which is now freeware). Elder Scrolls could have Arena + Daggerfall, etc.
This way the classics get distributed but it's not just free bandwith for anyone who wants to grab it. You'd be paying the $6 for the goodies and the work that gets them working on modern systems, and probably wouldn't feel ripped off because you're getting more than one game.