Plenty of people live in the shops/restaurants they work at, which is why they put makeshift blinds over their windows at night. A lot of dodgy things like that going on in the 'jing.
Indeed, like Gutter oil [0].
I really wish I had read that article prior to my trip to China.
Even expensive hot pot restaurants got temp closed for using oil from questionable sources, so just paying more is not a guarantee for better quality ingredients, although eating fried food from makeshift street restaurants is almost a swill oil guarantee.
I have never heard of sunshine kitchen, but I don't live in BJ, so that might be why.
Western countries have their own questionable oil though:
http://www.businessinsider.com/fake-olive-oil-2012-1?IR=T&op...
http://kellythekitchenkop.com/the-olive-oil-mafia-be-aware-o...
But you're right, capitalism causes cost-cutting measures all over the world. However dangerous. Not just in Asia.
Also, the more official-looking temporary housing for construction workers has windows, but it's pretty dense. All those dudes can fit their whole lives into a single duffle.