I rode year round in Winnipeg, Manitoba for many years, and never, ever used studded tires.

I rode a mountain bike with 2" tires, and just simply flattened them in the winter.

Now fortunately, although Winnipeg gets really cold and often has quite a bit of snow, they plow the roads well so they are often bare and dry, even on days when it is -40C. If there happens to be some snow on the road, my tires handled it just fine.