Sure it exists, its called a Landscape subscription. Being able to manage both the desktops and smartphones/tablets for a company all through Landscape is actually kinda compelling. I know a lot of IT pros, since I used to be one before going back into programming and they universally hate hate hate iOS/Android/etc phones, because they is no good central management for them.
I'm sure for paid apps (on the desktop or phone or phone-desktop hybrid) Canonical gets a cut. The phone app store is much more a cultural norm than the desktop app store.
As a consumer, the idea that I could buy a phone with 64-128 Gb of flash and a quad to octo core cpu, 8 gigs of ram for under 500 within 5 years, which I could use with a cheap unlimited data plan (like t-mobile's $30/month 4G for the first 5gbyte and unlimited 3g after) and I could use it as a desktop or phone? Sign me up!