I had to research into the online English teaching industry for a work project. A lot of the schools are based outside of the U.S. - China, India, etc. Here in South America one of the biggest ones, Open English used to be headquartered in Venezuela, although I am not sure if they still are. In my case, I had to find examples of U.S.-based businesses and there weren't many. I am guessing with that business model, few companies are following U.S. labor law, even if they hire people from the U.S.