Where are you in Wisconsin and are you new to the area? If you are in Madison or Milwaukee the streets are cleared by plows like some sort of military invasion. My street is cleaned just constantly and many folks I know here in Madison drive around all winter on old, hardened, bald tires. I'm not advising that you try this, and I don't do it, but they seem to get by with it.
My last winter car had dedicated snow tires on it. For this winter I have two options, both of which have new "all-season" tires but not real winter tires. I've only had the Smart a couple of weeks.
We haven't had more than a dusting of snow so I haven't been able to try the Smart in the snow. When I was in high school there were still a few old 70s beetles around and I remember that with rear engine, rear drive, and skinny tires they hardly ever had trouble in heavy snow.
I'm looking forward to driving a car with plastic body panels - no rust creeping through. I guess time will tell if these cars, like Saturns, will rust structurally on the underside in such a way as to keep them from staying on the road in the long term.
Paul