You might be amazed to discover that those sites that let you download movies currently in the theater may not be legit:

That's correct: a website named PirateCity didn't get their booty legitimately? Well, there's always ThiefTown and BurglarVille. It won't stop sites like these, since you can't "seize" a site that isn't hosted on an American server, and the bosses are probably in other countries (cough Russia cough)

This is where people usually say "it's not stealing because no one has taken anything, just a copy of it." Good luck with that defense.