The reason is simply the work of an American evangelical organisation, Campus Crusade. Funded by its supporters and well-wishers, it sends teams around the world, even where they are not particularly welcome. There they record new translations of the film, organise screenings to inquisitive crowds in improvised cinemas, and distribute copies to whoever they can.
Rather than concentrate on places like the UK, its focus is on the far corners of the world, although it has of late been sending unsolicited VHS copies to US households.
Among the crusade’s goals are to make a translation for every language. With some 7,000 languages on the planet it has some way to go yet.