You always see a group of African men in traditional dress, complete with ray-bans and ornamental carved walking canes? You never see them dressed like that in Stoke Newington?
Used to work at an Airport and they have to revert back to the ethnic gear to get back in to the homeland , because when they are here they are doing all the things they are not allowed to at home !! So out with the girls, booze , gambling drugs etc . If they are in Arrivals they are meeting them to let them get in to the Western habits before they then go home !!
They are the mysterious shamanic witch doctors whose magical spells keep the planes in the air. Without them, all the planes would just drop straight out of the sky.