I'll tell you I'm not a fan of those sunglasses they wear, they aren't the best for preserving depth of field. If you want to prove this to yourself stare at some point on the ground in front of you as a raise and lower the lens, you'll see the point shift back and forth as you raise and lower the lens.
The problem isn't when they have one pair to wear for a long time, but they aren't made optically perfect so no two pairs are the same, and they change them under sponsorship all the time now.
If you don't believe me, given they reduce glare and increase contrast, ask yourself why they don't wear them batting?