Why does that matter? I've heard that arguememt for other industries, that workers should be paid a wage that they can afford the product they are making. I've never understood it though.
That just can't work. Imagine every Ferrari worker being able to afford a Ferrari. What would that mean for a price of a Ferrari, eh? The price would have to go up, and then the wages, and then the prices and so on.
My statement wasn't meant as a general argument, but was just referring to this specific case - namely, inexpensive fast food. In order for the comparison between American and Yugoslavian work ethic to hold, you'd have to lower the American salaries to the point where they cannot afford McDonald's food. Let's see how that impacts their productivity.