My opinion on DLC.

Okay, i'm kind of tired so if my wording is bad I apologize. But I know a lot of people are complaining about how they are selling a game that is non-complete. Isn't it possible that the game was complete but then they had an idea later after its released. Also for first day DLC couldn't it just be something some people may want and others don't? Like say for this DLC released first day contains zombies or whatever. Person A may not want zombies so they don't buy it. But Person B wants zombies and pays for it.

Lastly, I know these don't really apply to ALL situations but to some it does.