I did one of the first Transitions eyewear shops. Pay was $25. Had to send in the glasses but they would send them back and I would get to keep the glasses. Glasses turned out to cost over $400! Got the $25 plus reimbursement for the shipping and the glasses.
Then I got an email from the MSC, the glasses I received weren't Transitions, so they would not be returning them. The store had cheated me and put in lenses from a competing (and cheaper) company! (Actually, the store showed me the cheaper lenses - they were about $100 less than Transitions. I was supposed to object that I wanted the real thing.)
Since I wasn't getting to keep the glasses, the MSC sent me a check for $400. This was on top of the reimbursement for what I paid for the glasses and the shipping.
After Transitions paid out all that money they revamped the shop. Now no one gets to keep the glasses.
What happens to the glasses that are sent back? The frames can be resold - just pop out the lenses. Many places use stock lenses and if they aren't ground down too much to fit the frame, they can be reused. For anything that can't be resold, they can donate them to places like Lions Club or Feed the Children and take full writeoffs for their donations. These organizations take used glasses and can use a machine to figure out the prescription. Then they send them to third-world countries and they are matched up to people who can't afford glasses.
NOTE: I'm not on the forum every day. If someone comments on my post, I might not reply right away. I've been a shopper since 1991. I've never done any work for a MS company in any other capacity.