My parents' condo was set up with something along these lines: six zones (two channels per zone), and each one has a wall panel with an input selector, volume adjustments, and track skip buttons. As originally set up, it used an IR blaster to talk to a CD player. These days, we now have it rigged to the audio output from an Apple TV box.

If/when the box dies, it's unclear my parents would pony up for another one, versus cobbling something together from cheaper parts.