Any reason why?
I just wanted all the games quickly and easily accessible. If I or a friend said "what about Tron" or "tempest" ot "Asteroids" I wanted them all there and available immediately.
It is defiinatley cheaper, easier to maintain. And I like having a universal machine. I also like the look and the controls do not interfere with each other because there is not a situation where they are used when they would interfere.