It must have been "acceptable" for a couple of decades. When I was in Uni. almost 20 years ago, we'd all share scanned books between us. Don't think I ever heard "Oh, no thanks - that's illegal"
Well that's extremely easy for publishers to defeat these days. Just make all the homework questions online and put a one time use code in the front and lock essential course material behind the purchasw of a _new_ book. Lots more publishers do this then was probably 20 years ago.
