Are libraries unethical to use? You can go to your library and read books without paying for them.
Libraries aren't unethical, because they're just letting you borrow stock of books. There's practical limits on how it scales, and any impatient users might just buy the book. Once you can infinitely duplicate a work, it's not borrowing.
So what? I think, if you read a good book, learn something or are well-entertained, it's a positive externality, so there is no problem with people doing it for free.
The only real issue with IP piracy is when someone gets money by copying the works. Which were originally the cases copyright tried to prevent.
Maybe you can clarify why you see people doing these things for free a problem, when there is a net benefit to society and also you.
When people around me ask about how to "get into reading" I tell them to just find stuff they like online (via AA) or at the library and go from there. If you don't pay initially you don't feel as bad about trying things that may be "bad" or that you aren't interested in.
Publishers aren't just stealing money that should go to authors. We can debate percentages and such, but buying a book also pays the editors (who any author will tell you are just as important to a book as they are), the typesetters, the designers, etc.
In the more indie fantasy scene authors often pay for editing themselves out of pocket. Often the only "publisher" they can get is direct publishing through Kindle, which then locks them into exclusivity with Kindle/Amazon. It's frankly disgusting but it's a way to help them get paid. I'd rather kick these people $20-50 directly than do anything else.
Moreover, many respected academic publishers no longer provide proofreading or typesetting: they expect the authors or editors to commission their own proofreading, and the editors to just send in a PDF with camera-ready output.
For monographs, the “editor” that the publisher provides is only there to guide the author in producing their own camera-ready output, and does not actually do any work on the contents of the book. The publisher will hand off the manuscript to 1–2 peer reviewers, but those peer reviewers are unpaid.