I've spent some time travelling by matatu, which are small busses that many of the locals use. If you are health and safety conscious, stop reading now. They pick people up whenever hailed and at the side of the road if there's space, and how much space is left is indicated by someone I would have to describe as a sort of conductor. This person does not have any seat to themselves when the matatu is full. Instead they lean out the side and hold on. Can you imagine someone hanging outside a minibus in the UK because it was full? Oh, and when there was a vehicle broken down on our side of the road and oncoming traffic on the far side, rather than wait for a reasonable gap, the driver took us up onto the pavement. Still this is probably safer than the motorbike taxis that people are happy to just hop onto.