I know that it is possible to add users to your Plex home, but its not an ideal option for many. I feel that I have supported Plex and the users that I personally paid for Plex Pass for are not able to use it.
It isn’t a reasonable expectation for any of my users to spend 50% the price of Spotify for my limited music library.
I know people love them some Plexamp and I totally agree that it’s a very well designed app. However, music is just a nice to have thing for me. Between free options and good inexpensive paid options music isn’t as big of a need as tv/movies for me and my users.
I have a decent amount of music on my server and my users have listened to exactly 0 songs. Not sure if Plexamp would change that.
There’s a subscription fee to use the app they developed, Plexamp. It offers features that their other apps don’t. However, access to your Plex server is free. Those users can use the free Plex app or the web interface. If they don’t want to pay the subscription, they can stick with Spotify. If your library is so limited, maybe it’s better they do? Or, maybe they could also access other Plex servers which have a less limited selection?