German cars are built to a standard that you don't see in many other manufacturers. They are generally over engineered to a certain degree. What I don't like about them is that they tend to be too clinical at times. You'd have to shell out loads of cash to get the premium ones of the range to get fun - Mercedes' AMGs, BMW M series cars, and Audi's S series.
American is about brash raw power on the high scale spectrum. For an entry level German saloon, you'd get a premium V8 monster with the American. Sure, it won't handle as well as the Germans, but that what you get with the price. It is more bang for your buck.
To state that American cars are only functional, you're kidding yourself. There is a sense of pride. Why do brands like Cadillac do their testing at the Nurburgring in Germany for their high end CTS-V cars? Then you are forgetting about the American hotrod scene and muscle car scene.
Unlike the Germans, Americans like to tinker with their cars and do modifications. Personalize their cars a bit. Those who buy American cars are more blue collar. But that is what is great about it.
Because they are all blue collar, they became popular. Now we have iconic American cars like Mustangs, Challengers, Chargers.
The only really iconic ones from Germany are BMW M3, M5 and the Audi Quattro. Mercedes' AMG cars are great, but not iconic. Perhaps in 20 years time, we'd be talking about the SLS like that. But that is about it.
German manufacturers cater to the side of the white collar individual. This is a man, who wants everything sorted before he leaves the showroom. He is not the kind of man that will spend time in the garage tinkering with the car. More likely just washing it and giving it a good clean. More often than not, he is the sort of man who'd pay to the guy owning the Charger to wash his car.