Your examples seem to be pretty small corner cases. I'll add one though: when I got the Adobe Lightroom beta, I got executables for Windows and Mac. And with my upgrades, I still get both executables. But the elephant in the room at the time was that the vast majority of software was being sold into Windows boxes and the only upgrade path was up. the lateral transfer schemes were many and varied, but all trivial compared to the big pipe called Windows XP.
On mobile, these "corner cases" are the majority of sales: every year there is some "new king of the hill", from random Nokia or Motorola devices, through Palm, Windows Mobile, and BlackBerry.
And, even on desktop with our example: Windows itself was the lock-in, not the sale; if a competitor to Windows did show up, the apps would rapidly move (and were in fact already selling both executables): if the sales were caught up in a monolithic App Store, users would balk at developer's inabilities to give them upgrade discounts, and are much more likely to stick to their platform.
I was just aiming for the cornerstone of your argument
> cross-device upgrade pricing was very common
Perhaps from within the industry having a lateral path was a common denominator, something every company had, and in that definition, it may have been "common", but not from a consumer perspective. The opportunity to buy PC software for a Mac was quite unusual for a consumer. There are still plenty of full time Windows folks thinking about getting Macs and asking their friends "Will I be able to use <app> on it?". Maybe not in SF, but most of the people I work with (and we're talking doctors, military planners, etc) are still in a Windows world, at work and at home.
My argument mentioned Windows and Mac only because most people are more comfortable with that example. As end-to-end App Stores have only become popular recently on mobile, I only consider this conversation to currently apply there. However, the premise of the Mac App Store also /assumes/ a non-Windows-dominated world /by definition/, so I fail to see why you feel your comment attacks my argument... :(.
