I have perscription sunglasses. There are times, when I go into the store to drop off a payment or pick up a perscription at the dr's office or pay for gas, that I don't switch back and forth between my two pairs. Quick in and outs, doesn't bother me in the least.
Now, if I see someone, which is usually in the 20something and younger age, walking around the mall or store wearing them, I think to be that young and full of myself to think that it makes me look hip and I am all that important that I need to wear shades inside to keep the people at bay. You can tell the difference between those that are perscription and those that are just pricey sunglasses.
I will also say, that one time my regular glasses broke and in such a way that you could not quickie fix and wear them. I had to go three days wearing my sunglasses every where. But I limited my running around, so that I wasn't wearing them outside at night and we didn't do any shopping.