Cloud services arent a good option for many. I dont prefer to stream my music of movies because it would eat all my data and would cost me more in the long run to get more of it. Many are trying to keep their costs down.
I didnt like Spotify and even if it were good, it is still the same thing. Google play Music is good but again, it uses data.
except spotify doesnt actually use your data (assuming you have "offline mode" enabled at all your playlists, which is pretty much standard)
i hate the fact that people dont give spotify a chance. it is by far the best music option out there, right now. so no, it doesnt drain your data.