In the 70s and 80s, soft drinks (at least in California where I lived) were packaged in really heavy, thick glass bottles. You paid a deposit on purchase, and a refund on turning it back in, and then the bottles were cleaned and reused.
These schemes have seemingly all disappeared. Many or most states still have deposit programs, but the intent is to recycle the glass, not to reuse the original bottle.
Reused glass milk and pop bottles here in the UK didn't seem different in weight or thickness to non-returnable bottles of the same era. They've all got thinner over the years. The oldest milk bottles I can remember, from the 70s, were indeed quite chunky but they'd mostly gone by the 80s. No idea how long they'd been around though.
The last fizzy pop refilling scheme I know of died about 5 years ago, leaving just a few dairies using it for milk.
Soda bottle deposits are effective and don’t get shipped off to poor countries.