Most independent bookshops don't solve the problem you're describing. They just buy the same books from the same publishers as everyone else. They don't create any variety. It's the same books!
Most of the time, I don't go to the bookstore with a particular book in mind. Instead, it's a Saturday morning and the weather is nice, so I want to go for a walk somewhere. The bookstore is a good choice, and maybe I'll find an interesting title there. If my bookstore shuts down, I lose one more important walking destination.
Unfortunately I can't buy that experience on Amazon, even with same-day shipping.
This might be a condition particular to walkable cities, though. I wouldn't drive to a bookstore.
Of course Bookshop doesn't help here either, but if it can keep their doors open then I'll be able to keep walking through them...
Most independent bookshops don't solve the problem you're describing. They just buy the same books from the same publishers as everyone else. They don't create any variety. It's the same books!