True, though if I were the "music czar" at Apple, I'd integrate Remote.app into Music on iOS (preferably replacing the Music interface with Remote's, at least on iPad, though admittedly this is a matter of taste) and add Remote client support to iTunes on the desktop.
My mom still has trouble understanding the difference between playing music on Mac iTunes via Remote from her iPod touch, and playing the same music, through the same AirPlay speakers, from the same(ish) library, via iTunes Match, and in principle, she shouldn't have to (this is admittedly tricky to get right for corner cases, but in the common scenario where desktops running iTunes never vanish and all songs are assumed to be in iTunes Match, there should be some simple logic to optimize the mechanism given only "song" and "speakers", to avoid stuffing an iDevice with music from Match and draining its battery when all the music required is already available locally on a Mac running iTunes or even via iTunes Match from an AC-powered device like Apple TV).