Nairobians on average prefer dating a woman from their communities if not a friendly, ‘wifeable’ tribe. Kenyans are that tribal. So much so that there is even an unspoken but publicly acknowledged warning for men from Western Kenya against marrying women from Central, especially from Kabete.
It takes a lot of defiance for men to go against the societal grain. Similarly, women from Central are often warned against men from Western, certainly citing clashing cultural practices, like wife inheritance.