Today's public service announcement, by Virginia Postrel: "Recycling Eyeglasses Is a Feel-Good Waste of Money".
In a paper published in March in the journal Optometry and Vision Science, four researchers compare the full costs of delivering used glasses to the costs of instead delivering ready-made glasses in standard powers (like my drugstore readers, but for myopia as well). The authors find that recycled glasses cost nearly twice as much per usable pair.
Glasses (which we should probably call "polycarbonates" instead) are pretty cheap to manufacture and distribute in quantity these days. From the linked article, it's amazing how much wastage there is in the process of recycling this kind of product.