The only retail bookstore within reasonable walking distance of my house was a Half-Price Books. It opened with the strip mall it was in opened several years ago. I've bought and sold many things through that store, not just books. Today, I got an e-mail telling me it closed for good (and telling me where the nearest stores now were; both are at least 20 minutes or more away by car).
The e-mail explained that the store did not enjoy sufficient traffic to stay open. That I can believe; the demographics of my part of the Twin Cities shifted downward over recent years, as many non-European peoples (never known to be great readers) moved in, and the long-standing whites are moving away. Couple this with the continued domination of Amazon, and the same retail collapse that destroyed Borders (and eats away at Barnes & Noble) won't spare used bookstore chains either. (Nevermind small independent stores.) Given that, of all the stores in Minnesota, only my local store closed, I can safely claim that demographics from peoples that read to peoples that don't is a big factor- but one unstated by the District Mananger in his PR release.
And then I looked at the remaining bookstores in my neighborhood. Somehow a comic shop and a general second-hand store got roped into "bookstore", along with a private antique dealer operating out of his home. The only proper bookstore is a family-owned and run printing business that serves the local churches in the area, so they don't sell anything I'm interested in. I am now in an unserved neighborhood, like North Minneapolis.
See, that's the flipside of the panic over Amazon. It's not just Amazon sucking up the business from those who would otherwise go to retail stores, but also the change in the makeup of a local market from people who care for what you offer to those that do not. You can adapt to the former, but the latter? Reliably kills. Even when the changes don't result in violence, they do result in other changes that aren't good for those affected, and this is one of them: the shift in businesses present.
At least my local library is in no trouble, yet.