This used to be true.  There were some Chinese companies that employed foreigners that would exploit this loophole by having the foreigners import an expensive car duty free, then turn around and sell the car for a tidy profit.  They changed the law a year or two ago.  Imported cars are now subject to the usual duties, regardless of who does the importing.

I made some initial investigations when I came here two years ago as I then had a very nice Mercedes paid for and the second hand market was awful, so I thought about importing it. I was advised that import duties on cars are punitive i.e. 100% plus.