I think we all know piracy is not theft. It's robbery and murder at sea. Infringement is not theft either as best I can tell. But ask a lawyer if the question pertains to your specific situation.
I just recently went to a RMS talk, and this is what he said too. (I paraphrase)
Piracy is people in boats killing other people and stealing their stuff. What about software piracy? As far as I know, pirates use guns and boats, not software.
What people are talking about when they say "software piracy" is "sharing".
