> someone found the good interesting enough to buy it in the first place (1st curation)
I wonder how this is offset by someone finding an item not worth enough to keep. But maybe I underestimate the generosity (or need for income) of the typical person visiting secondhand stores to offload their stuff.
Some (many?) book stores do a lot of their intake via estate sales, not just buying from walk-ins. That gets them access to lots of interesting and well-cared-for, if sometimes niche, collections at low prices.