As for illegal downloads, I don't know if they are primarily to blame for the crisis the music biz is in. I'm sure it's due to a couple of reasons why sales figures decrease. As for bootlegs: Those who claim they would never listen to any obviously don't know about the joy of discovering some rare gem and I wonder if they are really interested in the music. Not everybody is fortunate or old
enough to have seen and heard their favorite artists live when they were in their prime. Fans have always provided each other with inofficial live or rare studio recordings. They may be in circulation without the approval of the artist but they usually don't cause financial losses, they rather increase the interest in the artist, in my opinion.
Ripping new, official releases and make them available for free to everybody is another matter, that's indeed theft. If you put a lot of time, effort and money into something in order to sell that product and make a living from it, you wouldn't be pleased if someone else took posession of it and spread it without your consent.
The trouble is, it's not possible to suppress illegal file sharing entirely and some decisions of the artist / record company even prevent people from purchasing a product. "Exclusive" releases, for example. I guess most people on this forum would like to
BUY Boneyard or the B-Sides to
If I Can't Have You but they can't because they live in the "wrong" part of the world.