I guess I personally don’t really care about the legal aspect, I’ll make my own moral assessments on what I find reasonable to pirate etc. regardless of legality. Law only occasionally overlaps with ethics.
But on a philosophical level, a rethorical question I ask myself is; what does it really mean to “own” anything digital? I have to ponder on that for a while.
Devil’s advocate: you obviously own the physical media that constitutes the book, but do you really “own” the contents of the book if you’re not allowed by law to make a million copies of it and sell them?