Online music works nice as long as you're in a covered area (and the data traffic is of no concern). This is true for California highways but is often false for New York subway. This can also be an issue if you happen to travel abroad.

Spotify does not have a quarter of my music collection.

How hard is for some people to understand that whatever suits you, doesn't necessarily suits every single living person on this planet??? get out of your tiny little bubble for once, please.

I don't see any value for me in spotify, for example. In circles around me, spotify & co penetration is well below 50%, albeit most know about it.