The multiple cartridges is splitting hairs. Often they just output at different television standards or fixed a rare game breaking bug. They didn't add a new character or change how many are on a team, which is a fundamentally different game design.

If you sit two people in a room long enough with Third Strike, they will end up playing Yun and Chun-Li. If you sit two people in a room long enough with MVC2, they will end up playing Magneto, Storm, and Sentinel. No one had to tell me to play Fox in Melee before I had any idea that there was a Melee "scene"; the rules of the game steered me that way after hundreds or perhaps thousands of hours. That's what you preserve when the game can still be played.