Being force-fed this kind of thing is pretty unpleasant
If the was Microsoft, and you didn't know better, then perhaps it's fair to say you are being "force fed" this change. However, this is OSS, and nobody is forcing you to use Gnome Shell. You have options: stick with Gnome 2.x, use XFCE, KDE or any of the other window managers available. Just stop whinging about how you don't like it.
MS has no right to decide which part of their operating system I am "permitted" to use
Why not? As you say, it's their operating system, not yours. If you only pay $15 for a cut-down version of the OS, why do you think you're entitled to more than you paid for?
So why would anybody upgrade? Because the only real reason people ever upgraded their (Windows) OS was security (adjustable UAC helps with that tremendously) and UI.
The reason most people upgrade their OS is because their new computer has the upgraded OS pre-installed.
With your bare hands?!?