I would have taken both and left a note, then returned to do a bit of postering (especially if we're talking about glasses that aren't cheap gas station disposable things).

Those glasses might have been expensive, or they might have been fairly cheap but important to someone to be able to function and despite being cheap in a relative sense they might still have been costly for that person (or it might have taken a lot of effort for that person to acquire them due to needing a prescription and getting a custom order or whatever.)

One thing that is important to remember is that we are all ambassadors for radical politics, Marxist or anarchist, and that we need to act like it. Yeah, that money would be nice to have yourself but your instinct that the person could have needed it more is the right one.

I don't expect the revolution to kick off tomorrow and I doubt that you're going to find yourself in the same industry trying to unionise with this person but that doesn't matter. Imagine what difference it would make if this was the case - having a person who is naturally inclined to your cause is invaluable.

I have a real soft spot for Sikhism and in times like these I reflect on the reason why they wear turbans, amongst the other outwardly-visible signs of their faith. I also try to remind myself of the fact that, although I don't have the same sort of outwardly visible signs of my politics, I need to do what I can to be the kind of person that others go to because they trust me and they know that I will do what I can to help them.