Still don't condone book piracy. It hurts authors, hurts my friends and colleagues.
If you think you have an exception that justifies it, keep it to yourself.
Some of it is righteousness trolls or jerks waiting for a target.
But I think a lot of it is people feeling guilty and wanting to justify themselves and receive absolution.
But the fact of book piracy hurts book sales. It's not an industry where "try before you buy" leads to better sales, statistically.