In the legendary movie Tropic Thunder the following conversation takes place:
"What do you mean, 'you people'?"
"What do YOU mean, 'you people'?"
But what DOES he mean, 'you people'?
This is a race gag. Tugg Speedman is referring to the group collectively as being unadventurous, however Kirk Lazarus gets super-defensive about being referred to as "you people" (e.g. he implies that Tugg meant "you black people...").
Meanwhile Alpa Chino steps in to take umbridge at Kirk getting upset over Tugg's perceived 'racist' language given that he isn't actually black but has merely had a skin darkening treatment.
We're laughing at three things here;
Kirk being so "in character" that he's started to become a stereotypical angry black man, acting super-sensitively toward perceived racism, even where it's clear that none exists.
Alpa's disgust at the fact that Kirk (a white man) is mistakenly accusing people of racism.
Tugg's discomforture at being accused of racism (by someone white).