Often local booksellers will have the ability to order pretty much anything in print too. Here in the Netherlands there are only a few exceptions I can't order¹ locally, and even then I can usually find them on the national Amazon alternatives (i.e., Bol.com, which sucks, but isn't nearly as evil as Amazon).

For affordability I would recommend anyone interested in reading to visit secondhand book fairs for the breadth of titles available, and yard/church/jumble sales for the chance finds. Instead of buying a book immediately when you come across a title you like or got recommended, maintain a wishlist spreadsheet and sync that to your smartphone or print it when you go hunting for books. The author of this article follows Umberto Eco's philosophy of book hoarding (as they should, and as I do), so they will have quite the collection to pick from already. Delayed gratification for any desired title is totally compatible with that.

And obviously: if you can't afford local booksellers, join a library — that is way cheaper than Amazon, and better for all concerned.

1: Frustratingly, this includes the mass paperback editions of Brandon Sanderson's The Stormlight Archive series.

If you order from your local bookstore a book which is being sold on Amazon as a PoD copy by a major publisher, what do you think happens?

They don't have a separate manufacturing process for mom-and-pop bookstores. Amazon do the printing and the logistics but deliver the book to the store instead of to your house so that the store can hand it to you.