Cham Charm is one of many businesses in town run by the Khai family, under the name of the Khai Silk corporation. Apparently the head of the family makes most of his money (and they have an awful lot of it) selling silk overseas. For some reason his income is not entirely legal under Vietnamese tax laws, but through a loophole he is able to spend it on property. As a result what he does is build absurdly luxurious establishments (mostly restaurants), and when he needs a cash influx he simply sells one.
There seems to be a new Khai Silk restaurant opening every few months, and there is one near my house that usually has a Rolls-Royce parked out front. Charm Charm is no exception from this opulence; in fact it's one of the most upscale restaurants I've ever eaten at.