You pretty much summed up managers that have most of their employees on H1-B in the US. I know multiple managers that offload most of the work to the Asian immigrants on the H1-B visa, have them work 10+ hours a day and know that they can get them to do anything they want, because if they don't, they are scared that they can get fired and have to leave the country. I know multiple friends who silently work on weekends to potentially avoid being fired and leave the country!