So do pickup trucks only operate in niche roles outside of America? It can't be as simple as cheap fuel and wide open spaces?
IME they are niche roles only, typically the niche role of “must compensate for penile issues while being just practical enough to satisfy the taxman it’s a work vehicle”. Or as mentioned before “i’m too insecure to just buy a van”.
This is what people outside the US typically use
Much more load space and probably more payload too, on a smaller engine and the same physical footprint. Available in larger versions all the way up to requiring a commercial licence, and all the way down in size until the little sedan deliveries take over. Dropside, tipper, crane, box, duals, 4x4, you can get everything imaginable in pretty much any wheelbase you wish. Ford Transit is the classic single-name example, the VW T5/Crafter does it over two ranges.