How do paragraphs 4-5 of the cotton club contribute to the key concept of the article?

this is Paragraphs 4-5
The Cotton Club was “whites-only” — only white people were allowed to come inside and enjoy the atmosphere and entertainment. On one hand, this rule was not too surprising, because during the 1920s most of the U.S. was racially segregated.
White Americans did not want to see African Americans in their social gathering places.

But on the other hand, the rule was quite surprising. First, Harlem was about 70% African American, yet none of those African Americans could go to the famous club right in their own neighborhood. Second, most of the performers at the Cotton Club were African American. The managers coordinated this intentionally.
Madison wanted to give “authentic black entertainment to a wealthy, whites-only audience.”