This is a good point. I wear uninsulated boots and a pair of wool socks when I'm elk hunting in the late season. I don't hardly ever stop moving so my feet never get cold. I save the pac boots for waterfowl and coyote hunting. Most people would probably be more comfortable with at least a little insulation in their boots, though, like 400-800g since most people don't want to work hard enough to keep their feet warm in uninsulated boots all day.

If the snow is going to be deep, just buy a pair of gaiters to keep it out of the top of your shoes.