The reason cars are kept spanking clean is because, like Mary said, the police will fine owners with dirty cars. Also, the roads and the environment are extremely neat, unlike here.
In Muscat, my dad washed our car hardly once a month and even then, I used to wonder why he washed it because the car used to look pretty neat to me.
Here, one hour after I wash my car, my car is covered in a fine layer of dust and after one week, the car looks like it hasn't been washed in ten years.
And Hyundai Sonatas are not premium cars anywhere else in the rest of the world, just like how Jettas and Octavias and Corollas and Lancers and Civics aren't