People who wear shades indoors/at night/in cloudy weather get weird looks from me - but I'd never say anything to them face to face unless they were a friend I was giving shit to. I think that indoors (95% of the time) and at night there is really no excuse for keeping them on. In cloudy weather the UV rays are still there, but Jesus Christ the UV rays aren't going to make you go blind just walking down the street for a cup of coffee. I find that the people I personally know who do the sunglasses overkill are doing some combination of trying to be unapproachable / trying to be "cool" - like the poster above said, it looks douchey. And strangely enough its girls who mostly do this I've found, and yes they look like douches or the female equivalent of a douche if you think being a douche is a masculine thing. If you're running inside the gas station to pay for gas, fine, no big deal, but if you're in a place for over a minute, just take them off and tuck it onto your shirt collar, belt loop, or push them up on your head. There is something to be said for being able to make eye contact with other people. I can understand wanting to be left alone outside/in a public space, but indoors it just looks like you're up to no good whether or not you really are.