PacoTaco
500+ Head-Fier
I'd wager the average recording artist isn't making near what Taylor Swift does per album. Years ago I had the averages broken down for me by someone from the CRTC for a class I was in, I don't remember the exact amount the average artists were actually making on a CD but if memory serves it was well under a dollar per CD.
Even if it was a couple cents, it would still be many times more than what spotify gives per listen. It's better for smaller bands, but for bands like Tool and Foo Fighters and artists like Taylor Swift and Ludacris, they lose a large amount of money they could have guaranteed by CD/iTunes sales that people would have otherwise bought as big fans.
It's like Steam. It gets a smaller guy's name out there, and could be considered just the cost of advertisement. But for a big company? They don't need that kind of thing, so some pull out of there to make more money off physical sales or their own platform. Steam, however, has enough sense to discount AAA publishers.