To further add to CB's post, American mainstream white culture is a culture born of the assumption of plenty and the humor that it most often produces is either ironic, nihilistic, or petty. You could compare it to the European philosophers tendency towards atheism, nihilism, and materialism.
In the same way that Christianity thrived under persecution, Black culture has been allowed to more distinctly develop based on commonalities in the Black experience, and thus is more relatable by the average person since it is based on concrete examples and common sense.
Unless they are going "white people drive a car like this" "brotha drive a car like this". "White people walk like this" "brotha walk like this".
And @ the Simpsons reference CB, I think they were being sarcastic....implying that it wasnt true.
