Sunglasses on cloudy, rainy days

I’ve been noticing lately that there are a lot of people that wear their sunglasses on the cloudiest of days while driving. Is it part of that days outfit? Is it out of habit? Do they want to look stupid? Seems to me that people would have an easier time seeing in front of themselves if they didn’t wear the sunglasses when it’s dark and gloomy out. Anyone else ever notice this?