I just think about all the retread debris I see on the highways. It comes from 18-wheelers, mostly.
New tires for me, thank you very much.
Not all trucks. I think it's just that most people who run retreads on cars are driving older vehicles and don't do a lot of prolonged highway driving.
Some years ago, on a cross-country camping trip, I was somewhere like the middle of Kansas in the middle of Summer. I was driving about the speed limit, and an older Mustang blew by me like I was standing still. About 20 minutes down the road I came upon the same Mustang, disabled on the side of the road. Right rear tire was absolutely shredded ... and it had been a retread. Heat build-up just killed it. Turned out to be a young couple on their honeymoon. Lug nuts were rusty and so tight the guy couldn't get them loose with the flimsy "wrench" that was built into the jack handle. I had a 4-way spanner, so I helped him change the tire, including having him pull the dip stick and put a drop of oil on each stud.
No retreads for me, thanks.