I think you'd be surprised how many companies support iPhone due to sheer employee demand. My employer was a closed PC shop but at least half the staff now have iPhones - that can't be ignored.
And if the AVP offers pro apps that others can't match, companies will buy it.
Not in the volume that they buy iPhones. Everyone has a phone. Buying iPhones is low risk. Putting your workforce into goggles is a dicy proposition without the obvious benefits of a work phone.