Because sometimes I'd want to play vanilla. If there is a bug or glitch introduced with installing DLC then that would be a way to fix it. You couldn't use the old save, obviously but I really would've liked the option to turn DLC on and off. This applies more to Dawnguard than the other expansions, mostly because the Hall of the Vigilant gets destroyed. I feel like this was a dick move on Bethesda's part because you lose one of your Restoration trainers and I kinda liked the place.What? Why?
What is the whole reason of wanting to disable the DLC?
If you did that, then one of two thing would happen:
1. Your save would be unable to load, as it is missing the DLC, and cannot load any of the DLC's files (obviously, because you have it disabled/deleted)
or
2. Your save would load, but you would be missing any of the DLC equipment/quests (obviously), and when the DLC is reenabled/redownloaded then it will be like you are starting over
I really don't see the point of doing that, though.
Because sometimes I'd want to play vanilla. If there is a bug or glitch introduced with installing DLC then that would be a way to fix it. You couldn't use the old save, obviously but I really would've liked the option to turn DLC on and off. This applies more to Dawnguard than the other expansions, mostly because the Hall of the Vigilant gets destroyed. I feel like this was a dick move on Bethesda's part because you lose one of your Restoration trainers and I kinda liked the place.