Is my manager reasonable????

i recently start working in a supermarket in Singapore. There is a very strict manager work over there. If she scold people with reason to back up with, i can still understand. But she not onli scold the cashiers and packers there, she also look down on those china people who go there to work as cashiers. For example, if they go on medical leave, she scold them and criticize them. U think this fair.