One thing I found that extended the life of ALL my work/play eyewear is using the dreaded "nerd" leash.
I was forever dropping them, sitting on them or leaving them laying around which often meant they were laying on the lenses which resulted in scratches and ruining them for everyday wear.

When I put on a pack/ sternum strap, I just hang the glasses temporarily on the bill of my fishing cap so they don't get damaged while adjusting the pack.

Little things, but they add up.
When they're not around my neck, they go in the little neoprene case they come in.