This is a great point. In addition, Spotify creates a much more distributed market for artists. I've found literally thousands of small independent artists that I would have never found through the filter of CD shops and record labels. Their service is curation, and it helps everyone (consumers and artists) -- except the record labels who lose market control.
I eyeroll every time I see someone here say "all the consumers are stupid because they don't behave exactly like I want them to behave, and I must be the right one"