1) Modern contemporary electronic music, which is usually available vinyl only.
2) Classic albums in their original form. When there's a remaster, Spotify typically only has the remaster, original was either never there or will be removed when remaster is out.
Now, when you start to invest to your sound system even a bit (not talking about 100k wires here), you notice the lack of dynamics in many remasters. The originals just sound better with good soundsystem, not so much with below-average systems.
When I listen to music, I like to have the best possible master from it. And preferably lossless, or that I have the control of the compression parameters and format. I guess Spotify will take the masses, but I'm not the only serious listener who prefers my own files and physical copies.
Streaming is handy, but you can do a lot of things already with big hard disks with your computers, some syncing NAS system (as in Synology), beets[0] and a big enough microSD in your phone.
[0] http://beets.io/