Redundant? And what option? How does that effect anything?
EDIT :
PS..It's an option.
Sorry, it was too tempting.
Because it's completely against the lore. And if you can't trust the lore from the game anymore, then the devs can invent whatever the heck they want without repercussions, and nuke the whole game series. The lore creates certain limits, in order to keep the whole thing under control.
Besides, daedra are a lot more powerful than the Nirn dwellers, and mostly evil. It just wouldn't make any sense.