I am unsure how you think that makes sense. Not trolling but seriously wondering your thought process. Sometimes areas aren't all that dark and you really don't need night eye or don't wish to use it. Night Eye makes things change color as well so you don't get to see things in their normal light. It isn't a matter of light and dark it is also hue which to me is a big deal. I don't always want to see blue. It's like playing a FPS and having nothing but green night vision, would you spend 64 bucks on a game to see nothing but green when the world is highly detailed? I don't think so, so no... It will be worth using and it is nice to be able to toggle it on and off. Also, people state no cooldown which makes it all the better than previous games.
Yeah, for some reason I was under the impression that Khajiit could just have Night-Eye on at all times... which means day time looks normal... but night time and caves just look less dark.
Never played a Khajiit before... so I didn't know about Nighteye in the past. Just trying to decide if this will be my first Khajiit or not.