Also, I don't understand the presumption that independent stores are better on any of the dimensions that Amazon is bad. In my experience as a factory or call-centre worker, the smaller the business is the more likely it is that they will try to avoid tax on cash transactions, ask their workers to work unreasonable hours or accept average rates of pay that are less than minimum wage, violate health and safety laws, etc.

I’ve used https://www.betterworldbooks.com, they are a B Corp and donate a book for each book purchased.

Things like AbeBooks and Book Mooch exist. They just aren't as immediately convenient, so, the question is - as is often the case on the internet - convenience or morality.