They get plowed by the local precinct captains. Both airports get good attention but Midway had a plane slide off the runway and onto the street killing a baby in a car stuck in traffic a few years ago. That airport is only 1 sq mile and the runways are short. ORD has long ones with a lot of sliding room.
If there s snow on them, they get plowed. Planes get de-iced in the winter.
they are made into hot dogs. read the jungle and you will see it is true.