Relative to other things like travel, commuting, home energy usage, electronics, etc, I'm guessing the environmental cost of a pair of glasses is very, very low.
It is important to focus on effective actions. For example, a lot of people think that somehow recycling affects climate change, which (AFAIK) is not true in any meaningful sense. That isn't to say one shouldn't recycle -- there are plenty of reasons to do so in many cases.
Post-consumer paper can be recycled in to some forms of low-density card that doesn't require high quality pulp. Egg cartons come to mind, and as a percentage in some packaging, newsprint and sanitary papers. Post-consumer paper cannot easily be recycled in to anything resembling printer paper due to the contaminants. Pre-consumer paper is recycled heavily as it's of known quality.
I'm not aware of any plastics that are recycled in to the same form. I know that PET (1) and HDPE (2) are recycled in to fibres.
It's a similar story to glass, certainly where I live a large amount of glass is recycled in to crushed aggregate rather than new bottles. The energy costs of cleaning don't make it worthwhile.
I don't throw away my old glasses. I keep them in various places as backups, such as in car gloveboxes, in the home emergency kit, in a bag while traveling and so on.
When I was younger I used to tease my Mom & Dad for essentially treating their reading glasses like pens or pencils, and letting them diffuse around the house as the acquired new pairs.
Now that I'm in my mid-40's, I take it all back. Having a pair, even if it isn't the exact right one, always with reach is a godsend.
Me too. I have around 10 pairs, so I never find myself in a room/place without them. I like Dr. Dean Edell’s for their combination of style/comfort/build quality/light weight. $9.99/pair
Me too. Even though my eyesight continues to deteriorate, a pair of old prescription glasses is many times better than no glasses at all in an emergency!
It is important to focus on effective actions. For example, a lot of people think that somehow recycling affects climate change, which (AFAIK) is not true in any meaningful sense. That isn't to say one shouldn't recycle -- there are plenty of reasons to do so in many cases.