Break yourself in slow. The key is to be mindful. Try to eliminate the automatic habit. There are some times when you'll want the shades, but just not all the time.
Regarding shades, I don’t wear them often, but certain times of the year, and depending on which way I’m driving, they are a necessity to block out not only the sun but the huge amount of glare reflecting off other vehicles. When the sun is but a fireball sitting right near the middle of the road ahead of you, you need shades if you have any hope of seeing where you’re going.
And not just any shades, polarized shades.
Now, when I’m out working in the yard or doing other outdoor things, I generally do not wear shades. But they have their place.