Unless they have credit for writing the song, or self publish, the band makes most of their money from touring and merchandise.
BitTorrent isn't a zero sum game. It's difficult to prevent and any action upsets fans. Why not embrace it and get free PR. Meanwhile, the people that will buy it (or request it on a radio station, or listen on Spotify) need to be aware of the music. And both groups end up attending concerts. So it's really a win for the bands. It's the labels that are at risk.
David Lowery says that's not true. He says that your idea of how much artists make from touring suffers from cognitive bias: we pay attention to the anomalously successful huge touring acts, but that the reality is bimodal: a very few major touring acts, and then a huge cluster of artists who make less than minimum wage from even respectably attended club shows.
Neko Case made some comments to the effect of how much her returns were from touring _Middle Cyclone_. I went to that show in Chicago, which packed the large Chicago Theater. Neko Case was repeatedly featured on NPR and other media venues. She is anomalously successful. How amazingly lucrative do you think that tour was for her? Hint: if you're picking between being Neko Case and a senior engineer at Google just based on the money...
Of course, Steve Albini's famous "Some Of Your Friends May Already Be This Fucked" made much the same point about touring. He'd put it this way: if you're picking between being a midlist touring act and a senior manager at Wendy's just based on the money...
Meanwhile, the popular conception of how lucrative a label recording contract was is also mistaken, because it failed to take into account recoup rates and automatic per-sales royalties that are paid out even when albums don't recoup. In reality, the recording contract alone both financed the (very expensive) professional-quality recording of music and provided musicians with a base-level middle class income.
BitTorrent isn't a zero sum game. It's difficult to prevent and any action upsets fans. Why not embrace it and get free PR. Meanwhile, the people that will buy it (or request it on a radio station, or listen on Spotify) need to be aware of the music. And both groups end up attending concerts. So it's really a win for the bands. It's the labels that are at risk.