Here in New Mexico there's a long tradition of flat-roofed adobe house construction; the materials are abundant and it insulates fairly well (by the standards of the 1700s). But the roofs always leak because snow and rain don't immediately run off. Yet even though we now have modern building materials readily available, a lot of faux adobe still gets built especially in wealthy neighborhoods.
We have a saying: "New Mexico is a place where poor people want to live in a modern house with a pitched roof and rich people want to live in mud huts."