What I don't get is, pumpkins aren't spicy. Not even remotely. So what part of the plant does the "spice" come from? The vines? The leaves? The roots? Do they even have roots?
I think at the bottom of it all we'll find that so-called "pumpkin spice" is derived from utterly unpumpkinal - and possibly even unautumnal sources!
It should be looked into. But nobody benefits by looking into these things. As usual, its a hegemony of the status quo riding herd on a gaggle of vested interests to keep change confused, divided and unfocused.