The point was simply to lol at the Paleo prophets and groupies that demonize grains in our diet solely because the caveman didn't eat them.
I wonder how they prove that? The few frozen or fossilized ancients they have discovered didn't eat grains shortly before their demise, thus they can make blanket assumptions?
I see that societies that we regard as primitive don't have a great deal of grains in their diet, but, it isn't "cave days" now so who knows what grew then? And grains are not the only source of carbs. Potatoes, squash, bananas/plantains in warmer climes, and other stuff have carbs a-plenty.