Culturally Pondering: Why do we as Black people or AA's put behavioral and dietary boundaries on themselves?

OK I don't want to make this long so I am gonna get right to it. Black people often say things to each other who are out of the box of what is considered the norm of the black community as "acting white." Example if a black person prefers rock to say Hip hop or R&B. They are often told they are acting white. And if a black person prefers golf or Tennis to basketball they get the same label. Also If I order a steak, and I tell the waiter I want it medium rare. I am told that, that's how white people eat it or I am being white. Why do we as black people do that? I know this has been asked but not like this. It's like we put boundaries on ourselves and if one steps outside the boundary then they are called names or shunned. Your thoughts?