Then in the Arctic circle they can use dogs, which run on meat. In polar regions and Africa they perhaps use air transport more for longer distances. In the parts of Africa I have seen there are plenty of cars, vans and lorries for short and long distance travel and in rural and urban areas they use motorbikes too. As in urban areas the world over, cars are used for short journeys and public transport from the suburbs, not much different from here. In polar regions there can't be that many long distance journeys going on but for travelling on the Ice Road in Alaska they use huge lorries. In southern polar areas they seem to have specially built tracked vehicles as there are not many roads.
To explain the statistics, perhaps in Africa fewer people own private vehicles as they either use public ground transport or fly whereas in Antarctica there simply are not many people or roads, so not exactly comparing like with like.