Because blizzard conditions are nothing to mess with despite your poo-pooing it.
People where the worst of this storm is going to hit have neither the equipment nor experience to justify being out in it. Their vehicles have useless all season radials and they don't know how to drive in the snow, so make themselves a hazard to themselves and others. And the worst ones are the ones who think that because they have a 4 wheel drive SUV, they're invincible. I've passed enough of those idiots who blasted by me at unsafe speeds, with their SUV facing in the wrong direction off the road a few miles down the road.
So when they're in a ditch, someone has to go out and rescue them to keep them from dying of hypothermia or CO poisoning. And that takes time and expense from real emergencies.
Not to mention that when their car is stranded on the interstate, stuck in a snowdrift, which WILL happen with winds like this storm has, then they have to dig the cars out, one at a time before they can plow. It's FAR easier to plow and clear the highways without having to deal with the idiots who have no business going out in the weather in the first place.
You're from NY. You ought to know what happens around here when the first snowfall of the season hits.
All the drivers are like brain dead idiots who never saw snow before and forgot how to drvin in it since last March (or April, or May).
Not to mention DC area drivers are frequently from the south with no snow driving experience. Many years ago my late husband had a scholarship at a DC university. It was snowing, and almost no one was there. He went to the cafeteria and joined a table with 5 or 6 other people. The only people in the room. They started chatting. “Where are you from?” Oh, I’m from Michigan. I’m from Alaska. I’m from Iowa. I’m from Maine, etc. He was laughing about it when he got home. Now I’m only from New Jersey. But I was 10 years old when the “Big Snow of ‘47” hit. I can remember wading through snow up to my chest. When my father dug out the path to the street, we measured the snow as 27 inches deep, and I dug a cave in the wall for my 2 year old brother.