In the 2012 investor day Nu Skin published a map of their Chinese sales by region.

(Source - slide 81.)

Here is a map from Britannica of the population density of China.

On these numbers the women (and maybe men) of Western China are giant consumers of the product relative to population - indeed probably relative to anywhere in the world.

Nu Skin it seems has a knack of selling to Uyghur women.

Perhaps they could explain it one day.