Just an observation, and it may be just nothing, but have you went into a Chinese buffet in the last few years? I have--and noticed something, that for the most part they are all the same.. Has me wondering if they are controlled by the ChiComs and are an additional income stream for their development.. The chinese buffet craze came about within a few years of economic liberalization, before that they were virtually all sit down menu-based...
On the whole, doubtful. However, as with all businesses of this type, I would be suspicious of a small fraction of the illegal aliens working there. Some of them may be using an under-the-table "illegal" charade as a cover for something else. But in reality, the most espionage (as demonstrated many times by the FBI and US Atty's Office) is happening via other "legends." The most common legends used are students (here from the PRC on student visas) and professionals (here on H1Bs if worker bees and L1As if management).