It's not five minutes. When we get dumped on by a foot of snow about three feet of chunky heavy show is pushed about five or six feet into our driveway. The snow blower won't handle it and it takes sometimes a half hour to hour to clear it out.
Yeah, getting through plow detritus sucks. When I had my Civic, I wouldn't even attempt getting into or out of my alley if the plow had been by until I blew it out with the snowblower. Mine (good 2-stager) can handle it, but it still takes 5-10 minutes to clear a car width path.
Depending on where in the state you are it's only a few times of year, and then of those few times only a certain percentage will have you in an on-call situation. So it comes down to how many times of year this comes up versus how many miles you drive, and what you'd actually save in gas.
For example, a jump from 30mpg to 40mpg saves you $25 per 1,000 miles with gas at $3/gal.
Know how many miles you drive versus how many times you're on-call. Do the math to quantify it and make the choice.
If you do go the small car route, you also might find it necessary to keep snow tires around to keep enough grip to have fast response time even in crap roads, so that could also wipe the savings right there.
Since I only drive a few thousand miles a year, I'd personally keep the more capable vehicle.