I'm interested in your "east vs. west" hypothesis, but how did you arrive at it considering the enormous number of western street/snapshot/grunge/etc. photographers?
I'm aware of western snapshot photographers like Nan Goldin. All countries have photographers of all styles. My impression of east vs west mostly comes from visiting photo exhibitions and I do notice a difference between styles and what each culture appreciates most. I don't have the artistic background to truly articulate what is different. But I do notice many photographers in the west, like the person in this article, approach photography like painting.