The fundamental difference is that BT assumes you make a copy. Everyone who gets a copy has that copy forever, essentially gaining all the benefits of purchase. At a library, however, you get it for 3 weeks and then you bring it back. It's protected by the doctrine of first sale which says that I can do what I wish with the physical thing that I own, include lending it or reselling it. Digital copies are not "lent" they are copied and never need to be returned.
>Allow me to laugh, because the last people who benefit by this system are content creators. If you seriously believe copyright is, was or will be for creators, you're in for a bad surprise if you ever take a look at the history of what probably was the most harmful idea mankind ever allowed to happen.
This argument... is patently untrue. If I publish a book, everyone who buys a copy puts money in my pocket. Everyone who downloads it without buying it gets all the benefits of my work without compensating me. To make the argument your making is unfair to all the people who make their living producing content.
Here's the deal, I get your point. I agree with it. I think the content industry (I make a distinction from the copyright industry because I think copyright, in its intended form is a good thing) is crappy. It continually tries to subvert our rights (our right to the free flow of information, i.e. net neutrality, our right to the public domain, our right to use our content, our right to fair use, etc.). That's bad. But don't walk around trying to say that downloading stuff is not stealing. It is. Don't consume the content if the industry bothers you that much. Buy your music directly from artists, go to the opera, read only public domain books, whatever, hell, even steal it, but don't pretend you're doing the writer or musician a favor.