Your friend wouldn't be a classically trained musician who sight reads, would he (or she)?
Because it is important so people can play your music after the zombie apocalypse and all electronics are gone. Written music will survive like the cockroach. Your disks and mp3 player, not so much. Of course, this presupposes zombies like your music and can play instruments.
It is the same w/ videos - all the bad versions of literature will be gone, forcing the zombies to read for pleasure, instead of heating up some popbrain to watch Dawn of the Dead on a hand cranked projector.
Meanwhile, in the real world, you can copyright your music w/ sheet music, or just send the gubberment a CD.
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