They do more than cheating their own. Here is a list some of many that were featured in 60 minutes. Adding Melamine to baby formula to increase the content, using cheap Formaldehyde glue for laminate flooring, using cheap toxic dye for Mattel toys, importing high toxic metal in shell fish imports to the US, executing excellent physique inmates then plasticize their bodies to parade across US museums, adding hormone to live stocks to speed up maturity, using low gauge ground wire in electrical imports, engineered fresh produce for disease free crops, pirating all US digital entertainments, dumping below value technology hardware and construction materials to drive out US companies then to gain world monopoly and the list goes on.
US no longer has a granite quarry industry because the Chinese saturated the US market with it. It's cheaper to get a granite countertop than a Formica one. The same is also true for a sillicon chip in every cellphone and computer.
The Chinese can only produce and manufacture things base on existing technology. They are incapable in coming up with their own. That is why there are spies in US government intels as well as private sectors.