I don't think the majority of them do. I think that most of these urban-dwellers prefer to have sex with as many women as they can, which results in many out-of-wedlock births, and gives them "honor". Case in point is my sister - got mixed with up with some dirtbag who told her how wonderful she was, etc. She gets pregnant. When she arrived home, she discovered that he had been seeing other women the whole time with her. He has now fathered 5 children with 4 other women.
Also, look at professional athletes, and how many kids they have, and with how many different women. I believe that it has somehow become part of the black "culture" to just spread their seed around. Sounds stupid, but I don't see whites doing this on anywhere near their level.