@barryem. My intent was to take issue with only one statement in your initial post. That is:
A good person shares with friends. That's ethical behavior. It isn't always legal behavior.
Apparently what you meant to convey was, as per your latest post, that
"in most cases I don't think it's wrong so I should lend it".
My apologies if I took your statement too literally. It seems that we agree that what is moral and/or ethical depends very heavily on the context, and of course on our own individual standards.
I was definitely not attempting to equate sharing a book with larceny. Only "rights-holders" seem to be keen on doing this. Copyright Infringement is not larceny, whatever the advertising would have us believe. It may or may not be ethical, depending of course on the circumstances. My example is meant simply as an illustration that sharing with friends is not always ethical.
By the way, I like your Elmer Fudd avatar.