It's in the news today that six of the major internet providers have joined together to try to tackle internet piracy. Internet Piracy
Personally, I think it's the music and film companies just getting upset because they are losing some of their profits, which are way too high anyway. They are trying to claim that it's the artists that are suffering, but in fact it's them that are getting upset that people are able to get access to their products without paying them through the nose for it.
In many cases, the people sharing the files have already paid for the music or the films that they are downloading, but have lost their copy, or the disc has an error on it or something that means that they feel that they aren't really cheating anyone out of any money, it's just that they don't see why they should have to pay twice for the same product.
With myself, I have to admit that I have occasionally downloaded films made by a certain US film company that I outright refuse to give any money to as long as they continue to donate their profits to extremist right wing groups, but they do occasionally produce the odd good film, worth watching, but principles won't allow me to give money to those extremist groups, whether directly or indirectly.
If anything, the sharing of music files tends to increase the overall sales of that group or track, as people download it, listen to it, decide if they like it or not, and if they do then they then go out and buy the CD, whereas without them trying it out through the file sharing, they wouldn't have tried it out.