Guys think they can get away without plow Insurance because they know what they're doing. The trouble is, there are so many stupid drivers on the road and they'll get behind you when you least expect it. Not long ago a plow truck backed over a woman who walked behind it when it was backing while plowing a convenience store lot. It happened during a nasty snow storm when visibility wasn't good when driving forward, let alone backing. If I remember right she was killed. I don't know if the family sued but it wouldn't be a surprise if they did.