The Echo does this with Spotify too, fwiw. I ended up creating a separate account in my Spotify family for the Echo to link to Spotify, which is less than ideal as you lose your personal playlists, etc.
We actually canceled our shared Spotify account due to many similar friction points. The main benefit of Spotify was being able to discover new music, and I found it wasn't much better at that than subscribing to specific YouTube channels. The $10/month that I was paying to Spotify now goes towards about 10 DRM-free $1 songs per month, and considering how long I've been paying for Spotify, I think it's worth it. I imagine more of this $1 goes to the artist, too, compared to the royalties they'd probably have gotten from Spotify.
Same here. These services charge $5 more for a family plan, which lets you use five or six accounts. So you can make an extra account for your home devices, and then you have extra memberships you can give away for free to your family/friends. It’s not a great user experience but works well as a solution.