Grown men wear shorts.
Shorts in general are not as common in the rest of the world as they are in the United States. Grown men wearing shorts, especially, is just about unheard of. In most of the world, shorts are reserved for children and only in very warm environments. Americans tend to wear shorts at every opportunity, even when the weather isn’t all that stifling.
Pair these with some white socks and a fanny pack and you’ve just hit the trifecta.