@
Apple blogger,
@Brookzy's original answer was the correct one. Get a family plan. That gets you 6 concurrent sessions. They can be used by up to 6 Apple ID's or just one. I was previously on a friend's family plan....was how I was able to have music playing on my mac, Apple TV and iPhone at the same time.
Apple does NOT limit Apple ID's to a single session - except on the single user subscription.
As for the Mac and iPhone thing - there used to be race conditions with Sierra and iOS 10 that you could get around that with a single user account. Seems much more tightly integrated on HS and iOS 11.
Oh...and as to why a single user would want this? You have the music playing at your apartment, friends are over, you run out to grab a few things from the store. You jump in your car and turn on the tunes....boom!
Me, I think they should give single users two sessions....also you could have the Apple TV in the bedroom playing one thing and the Mac Mini connected to your AV receiver in the living room playing something else.
🙂