I live on a acreage, 17 km south of Calgary. It's colder here than in town and we have a ton more snow. When its -35oC and the wind chill is in the -40's I wouldn't go out in bare feet and neither do my dogs. They can get frostbite just as easily as us. They need to be able to stay out long enough to do all their potty business comfortably. In fact, I use them at any temp below -15oC to keep their feet safe. I have had frostbite twice before and it is a very unpleasant thaw. I will save my pets from that distress.

I see using the boots as proactive and preventing potential pain for the animal at the frigid temps.