Earlier quoted context omitted.
The most sustainable way to "buy" music IMO, is to pirate it, and then buy merch from the artist as support. Or just buy off Bandcamp if its an option.
I Don't Have Spotify should add Bandcamp support. Bandcamp is great for just playing the music too.
Buy it, download as FLAC, put in your preferred local infrastructure to play. Plex/Plexamp works well, as does local file storage and a good command line music client if you're less GUI-friendly or don't have the resources for running them.