Yep, we do!
In Montana (my area anyhow) most cars are sold with an engine block heater already installed. There's this wee little plugin that sticks out of the front of your car, usually in the grille somewhere, and you plug that in at night to keep your engine warm and keep things from freezing up. Most people, if their car didn't come with one, take the car to a mechanic right away and have one installed. DH has one, I don't - but I wish I did. I am the only one in our circle of friends who doesn't have one.
Our houses are usually built with a plug-in accessible near the driveway or parking area, so the cars can be plugged in. I have even seen little electrical outlets on posts near each parking spot at hotels and motels, to enable overnight guests to plug their cars in and be able to get on the road again the next morning.