Stealing IP
I thought the prevailing wisdom round these parts was that you can't steal IP, just infringe on it.
More seriously, a patent is a licence given by a country to prevent others using your invention, in return for your publishing the details. A US patent will stop others making, selling, or importing your invention in the the US. If you want to stop a Chinese company making it in China, and selling into the Chinese market (1 billion potential customers!), then you need a Chinese patent.
There used to be a stereotype that Chinese patents were worthless, so inventors didn't apply to them. That stereotype is now false - Chinese companies have lost infringement cases to foreign companies. But many patents don't have a Chinese equivalent, and are fair game unless you plan on exporting them.
For many companies it's actually the trade secrets which protect them. They have a good working process to make their product, and know all the little tricks to keep production going. Any company trying to set up against them has to go through all the hard learning that goes with setting up manufacturing, which takes time and money. Shipping the production line over, and then teaching them how to run it, provides a handy shortcut to learn all this.
So this is more about companies rushing to hand their IP over than having it stolen. Not that it matters to the folk on the factory floor when the company goes bust.