I care. I have iTunes on my Mac and Music app on my iPhone, why would i want another app for something i can already do and with much greater flexibility.
How is using iTunes on your Mac and Music app on your iPhone offering you "much greater flexibility" than the Sonos app that:
1) Integrates your entire system in a single app that allows for simple remote control of every zone, including:
-playing the same or different audio in each zone
-independently or combined control of volume of each zone
-grouping or ungrouping of zones
-joining or separating speakers into pairs or stand-alone output
2) Doing the above from any device on your network (i.e. - I can start something from my Mac throughout the house, and my wife can ungroup her office and play something different from her iPhone without my intervention - something that happened literally during the time I was typing this response)
3) Integrates your entire collection, plus streaming services beyond just Apple Music, into the app such that you can do #1 and #2 above from any device.
4) Allows you to pack up and leave the house, with the originating device, while still keeping the audio playing since the app is merely a remote control and the speakers are not reliant on them to continue to work. While this might sound minor if you live alone, in a household with several people it is an amazingly important benefit.
I know iTunes and the Music App can do some of the above. And, I totally get it if you are happy with AirPlay, iTunes, and the Apple Music app. Keep with them. However, stating that they offer much greater flexibility is just off-base and may confuse people that don't understand Sonos' features and benefits (and there is a lot of misinformation and misunderstanding out there, just read this thread and you'll see that).