In 1882, the U.S. passed the Chinese Exclusion Act and other laws that barred Chinese laborers from immigrating or becoming U.S. citizen. 

MIT legal historian 
Heather Lee discovered an important exception to these laws: Some
Chinese business owners in the U.S. could get special merchant visas that allowed them to travel to China, and bring back employees. Only a few types of businesses qualified for this status. In 1915, a federal court added restaurants to that list, leading to a Chinese restaurant boom.

Getting a special merchant visa was far from easy, Lee explains. Only the major investors in a restaurant qualified — and it had to be a "high grade," fancy eatery. .. . they couldn't do any menial work: no cooking, waiting tables or ringing up the cash register. ..  Chinese immigrants found ingenious ways to get around these hurdles: They would pool their money to start luxury "chop suey palaces," then each investor would take turns running the joint for a year or 18 months... Once gaining merchant classification they could then legally bring their relatives over to help run their restaurants.   

CLICK for  a video account of this analysis by an online 'magazine' reporter