What is "fine" is a values judgement. I would say that there's a continuum that goes from downloading an unapproved copy (worst) to buying the book at a local bookstore (best), and buying from Amazon instead sits somewhere in the middle. Somebody else might find the whole publishing industry gross, and decide the most moral choices are to either pirate the book or buy a secondhand copy.
>would say that there's a continuum that goes from downloading an unapproved copy (worst) to buying the book at a local bookstore (best),
Because you’re still fixated on bookstores, which tons of people don’t give a shit about. You’re incorrectly putting stuff on a one-dimensional continuum.
>or buy a secondhand copy.
Being a secondary market participant supports a market. If you don’t want to support publishers, it must be pirated.