Ah wait yeah I get you, the shop would have paid the label for the CD's so the only thing effected would be the shop itself.
I still think it's essentialy the same though, even if the label/artist isn't directly effected if you take from the store, you are still stealing the music.
Piracy is not theft - it's piracy.
(Not that I'm advocating it's correct or anything, of course.)
Like I mentioned above, even if piracy didn't exist, there's no guarantee people would buy the CDs, so it cannot definitely be a lost sale.
I suspect the reason why copyright infringement makes copyright holders angry is because there's a loss of
control. You work your butt off making music and someone listens to it for free. You've lost "control" of how your work is being "consumed" because someone has got it for free.
The one thing the Internet has got correct is the ability to spread media at stupidly-fast speeds. P2P is arguably the most efficient mechanism of getting a song out - it reaches thousands, if not millions, of people in the shortest time possible at the least cost.
For music, however, it spreads itself like word-of-mouth. The more people hear something, the more likely they are to buy your music (as long as it's good, of course).
In the past, people bought music from artists they recently-discovered through word-of-mouth and from hearing it from places like the radio. Today is no different - except for the fact we carry loads of tiny gadgets nowadays that have enough music to run a radio station for a whole day - word-of-mouth is less common, but hearing it is now more common in exchange. People hear things; they make like it; they buy related things.
This is why "music discovery" services like Spotify and Last.fm are so popular - it's modern-day radio that allows people to target their tastes.
It is possibly and contradictory but if you want something to sell, you want people talking about it - and in some ways, this could mean using piracy to spread the word.
In some ways, piracy is no different to my imaginary girlfriend and I listening to the same songs on an iPod via a pair of earphones, or by blasting the song on speakers at a party - lots of people consume the music, but there's only one copy! Piracy is just a series of huge parties with massive speakers. Music at parties is socially-acceptable and a brilliant way of spreading interest in an artist (see Vitamin C for graduation, dance tracks for parties, and so on) - so piracy should be somewhat embraced because it reaches a huge audience.
I would argue piracy should be cautiously embraced, and artists simply need to figure out how to get these pirates to pay.
At the end of the day, in the not-so-distant future, we will be exchanging lossless digital music at stupid speeds. Maybe HD (or greater) video too. There is little that can be done to stop it. The music industry would love everyone to go back to buying CDs - but it's not going to happen. Maybe revenues will plummet and profits will fall because prices are lower - but that's the free market for you.