You don't have to look to rural tribes to find this behavior. In Manhattan, "North" and "South" usually are colloquially defined with respect to the orientation of the island, not the actual compass directions.
And here in the vicinity of Santa Cruz, and going up towards San Francisco, "north" and "south" are often defined by reference to the labels on a freeway, even when that freeway in fact runs east-west.
Doing that in the Bay Area can have some odd results, as (for example) there is a stretch of freeway that is simultaneously I-580W and I-80E (and vice versa). Naturally, it runs almost due North and South.
