"...You can blow the snow out in front of you, so in effect you are moving the same snow a few times until it's clear..."

Yeah, but all that snow has got to go somewhere. If a total of 100 inches has fallen, even if you keep on top of it, the areas that are not being cleared (let's say the shoulder of a road), will have 100 inches of snow. Then you are trying to keep the road clear by blowing the snow off of it, it seems to me that the snow that used to be on the road has to go on top of the already accumulated snow. Making the 100 inches of snow taller and taller. I know that the 100 inches didn't all get there at the same time, but if there is 100 in the uncleared areas, and that is where the snow from the cleared areas must go...see what I mean???