In Poland there are many places where immigrants make kebab too, but even they put pickled cucumbers and red cabbage in it. You see, it's not about who makes it, it's about who pays for it. XD It's the same with pizza - we're used to lots of toppings and a good amount of sauce because, like Germans, we want our food to be good and filling. I once read an interview with someone running a pizzeria with genuine Italian-style pizza - he said people were complaining there wasn't enough to eat, so he had to modify the menu to satisfy the local tastes. Such are the joys of cultural differences. XD