I heartily support your rejection of the BSA's attempt to equate
forbidden copying with "piracy". I refuse to speak of "software
piracy", since real life piracy is generally committed using arms, not
using software.
However, the term "copyright theft" is equally misconceived. There is
no way to steal a copyright, since a copyright is not represented by
any specific physical object that one might steal. It is possible to
take someone's copyright through fraud. It is also possible to
intimidate someone into handing it over, as the major record companies
habitually do to young musicians. But theft of a copyright is
impossible.
Software theft is possible -- one could steal a CDROM, for instance --
but this does not involve copying, so it does not concern copyright
law.
What does concern copyright law is copying without authorization.
That may or may not be a crime, but it is never theft, as any lawyer
speaking seriously will confirm. To call it "theft" is to use that
word loosely in order to express an emotional position, on the side of
copyright holders against people who copy. I have a different view,
and the term I use to express it is "forbidden sharing".