Spotifyd is a Spotify daemon, not an user application. It makes perfect sense to run as a service. Though personally I would run it as a user service instead of a system service.

It’s in the image… % of citizens regularly facing package theft. Though that’s still pretty vague. How regularly is regularly? Seems incredibly high still.

You can easily request a free domain through services like duckdns.org. Might not be the prettiest domain name, but for these purposes it’s fine.