People warming up vehicles in frigged weather?

 Under normal driving conditions, there is no longer any need to warm up a car before driving it, even if you have not driven the car for days. The ...

Just waste4s Fuel and wears out engine Components for Nothing of Value

letting a car engine idle and not driving it any where wont make it last any longer it will help the exhaust rust quicker I hate old low mileage cars that have done nothing but idle and short trips they are all ways trouble when the next owner gets them and starts driving them seen it many times, if you not driving the car keep it in garage out of the weather if you want it to last.

Let can be it helps the oil move through out the engine and keeps the battery up if they let it run for half an hour or so:  so it can be just that!

Perhaps they will need to go somewhere later and they're just clearing snow & ice from the car so they don't have to do it later when they do go somewhere. Or maybe they're doing it just in case something comes up.

also, in many cases its easier to clear snow and ice during the day. Snow gets soft and slushy when temperatures warm up a little bit so its really easy to just push the snow & slush off the car. When the temperature drops back below freezing at night everything turns into ice and it becomes very difficult to remove. In some cases doors will even freeze shut so if you don't have remote start system you can't even get in to start the engine and try to defrost the car.

Also you don't mention your location but I know that here in Texas we're currently getting some of the coldest temperatures ever and many people are without power and therefore have no heat in their homes. A lot of people have been sitting in their car just to warm up, even if they don't go anywhere.

I think that learning patience is key.  I get up early to get out to the car early.  Not only is it important for getting the engine running, but also getting snow and ice off the car and to make sure that the heating/cooling system is working effectively and efficiently.  I have found myself putting the pedal to the metal to get to places on time, but that is very stressful and can cause an accident.  I prefer having time to spare, for my own peace of mind.  

Warm-up vehicle prior to driving

Henmueller proposed that vehicles should sit one to two minutes prior to driving in a chilly climate. At the point when temperatures drop to freezing, or when it's cool enough that windshields will ice over, the oil needs to heat up before it can move easily all through the vehicle.

You saw me do that last month, a couple of times,  to keep the battery from dying. I didn't need to go anywhere and have been isolating due to covid19 restrictions where I live. I tried a solar panel, but that could not keep the battery topped while it was cloudy for weeks. If you leave your battery flat, you WILL need to replace it. That costs a lot more than a pint of gasoline. I could have brought the battery in the house and put it on a charger, but I did not want to do that, since the last time I did that it took more than 6 hours The car is parked on the street, so stringing cords across the sidewalk for a trickle charger is too big a hazard.

You can prevent the engine sludging from condensation buildup, by running the engine long enough to burn off crankcase moisture. You really don't want a sludged up engine. 

Now there are people in Texas warming themselves in their cars since they're in power blackouts due to extreme cold weather. They aren't stupid enough to freeze to death in the house.

People sometimes do that if they think their battery or anti-freeze is marginal.  I'm amazed at the number of questions about frozen radiators, hoses, engines, heaters:  I realize that the cold is setting records in places - but don't those people use year-round coolant to prevent rust and to lubricate the water pump?

They THINK it helps the car it doesn't.  They need to drive it about 10 minutes just to warm it up.

When I lived in Germany one of my neighbors would hop into his (diesel) car, start it up and drive away within seconds.

I asked him about it later and he said that's what you're supposed to do.