Why do white people love having black people entertain them?

Everyone tries to deny racism these days or claim every black person is playing the 'race card'.Even in times past, a lot of white people were okay with black people if they sang or played sports or did some other entertainment bullshit.But once they tried to be scientists or doctors or business men e.t.c. they would face racially motivated obstacles.I see this trend still happening and I feel racism will never die if people of other races(especially white) don't stop seeing black people as only sources of entertainment.I won't bother asking anyone not to term this a racist question even though anyone with sense will see it's not.