Spotify is providing a much better service than radio and it needs the internet to function, but it also isn't as cheap as a radio broadcast. Don't judge the entire service by the free plan, which probably shouldn't have existed in the first place. But that's how most services attract their users these days, just burn money until you lock in enough people to start monetizing.
I'm on a family plan with a few others and it costs a few euros a month for each of us. Lets you download music too, so cell service isn't even required. I've never had an ad; people complain about sponsored recommendations, but Spotify is "pushing" tiny Japanese indie bands with less than 500 monthly listeners on me. All my Daily Mixes are similar deep cuts. I find it hard to believe anyone is sponsoring those and no way radio would ever have played any of these, unless it's a short-distance pirate broadcaster in the home town of these indie bands.
I don't know what the difference is between downloading and sharing libraries, but check out Soulseek. It's a little file-sharing program that lets others download directly from your music folder and vice versa. When I couldn't find an album on any torrent tracker, some hero on Soulseek had it. The main drawback compared to torrents is that you're limited to the upload speed of this one person, you can't connect to a dozen people with the same files and combine their power.