That's a bit too simple. People in inland provinces such as gansu or guizhou have much -much- lower purchasing power. I encourage you to have a look at a map of China with GDP numbers and then compare them to the US, Germany or Japan...

No need to look, I lived there long enough and have been to every province. Despite the still existing poverty is the internal market large enough already for many products.

However, China is not quite there yet when it comes to technology (hence the many Chinese students in Western universities), but they are well on the way.