I'll let T.J. expand on this or call BS, but it's my guess that in Montreal, it may just get too cold and have enough snow cover for much ice to form on streets. I had relatives that we used to visit in January each year and man it gets cold...but it stays really cold, with that crunchy snow, so there is not as much chances for the cycle of melt-freeze-melt-freeze that we have here in Chicago, where black ice (and brown slush) are a real problem.

PS: haven't been up there lately. I do miss the wood-fired bagels and the middle eastern pastry, tho.