On the first point, I was specifically referring to iOS apps, and you cannot "sell my corporate iPhone/iPad application" in the way you describe. Side-loading is only available to businesses with more than 500 employees, and as far as I understand, is only for internally developed applications.
Fair enough on the second, but it's tangential to the point. Apple constrains the distribution channels of iOS apps built using Xcode. This specific case is analogous to the iBooks Author tool restrictions.