I never thought of that. Black people don't shower and shampoo as often as white people because they don't HAVE to. Black African skin doesn't excrete as much oil as White European skin. If Black people shower and shampoo as often as White people do their skin dries out and gets itchy. We had a young Black woman living in our home for a while and this is what she told us. (And yes, she was meticulously clean.)
Anyway, it makes sense that if a person doesn't have to stick his head under water every day like I do he might not be as comfortable with water on his face.
It is also difficult for many African Americans to keep their hair without extensive effort when they frequently wash it in chlorinated water.
There is a reason behind the black hair product market. One of the reasons hair styles such as ‘corn rows’ are popular is to lessen the risk of drying out their hair.