I wrote a book on localization for Xamarin many years ago. I get about one email a week "inviting" me to join a book club. The well-crafted ones tend to impersonate an actual person on Goodreads.
At this point, I would happily give away my book, but Apress has the publishing rights. And since the sales are about a century away from being profitable for Apress, I don't see them letting me give away the book any time soon.