In Ditmas Park, Brooklyn, they are dedicated to the development of a multicultural population.
Second, the sign reminds me of the pitfalls of using euphemisms. What do they really mean when they say “multicultural”? They probably actually mean multiracial, but they don’t want to use a word with such harsh connotations (in the U.S.). So instead they use the word culture because it sounds nice and is often imagined to be restricted to things like language, food, clothes, and dancing (as opposed to inequality, oppression, and exploitation).
If they actually meant multicultural, then maybe the hat actually kind of makes sense! But I think they mean multiracial. In which case, see point #1.