In some Asian cities, it doesn't have to be a high end shopping mall. People with newer cars get approached by mall employees after they're parked, and are offered car wash service. You pay right there, and the car is clean by the time you get back.
Almost every shopping center around my place in Aus has this service.
But there's also a company that's doing incredibly well, offering to wash cars while people are at work. So basically car wash in the parking lot of office buildings.
I saw something the other week that I hadn't seen before. It looked like a personal trainer was working out a client in our office parking lot. He set up cones, heavy rope, some weights, etc.