At least once a year I have this conversation. It happened today while I was buying milk.
Shopkeeper: Why on earth are you wearing Sunglasses?!
I should point out at this juncture, it was currently VERY sunny.
Me: Erm, because the sun is shining and it's bright?
SK: But... It's Winter!
So, if you're planning a trip to either pole or even a mountain-skiing holiday, don't pack your sunglasses, you don't need them if the sun is shining in the bright cold areas of the world.