The government have been actively developing these cities and each one is a centre of production of one type of product.
One city is specialised in consumer electronics, another in rubber products, another steel working etc. Seems a good idea – reduces material movements in manufacturing process and concentrates expertise in a certain field.
The government also pay huge bonuses to companies who export. It means that companies can export at a loss (like the cheapo lights on Ebay etc) as they get a lump sum bonus based on the amount they exported which then gives them a profit.
I fear the Chinese will have total domination of pretty much every industry soon.
No problem, we just need to invent something to make that includes parts from two or three different Chinese Cities. That will mess with their heads. Rubber Coated, Springs anyone? 😉