In my culture, there's no particular stigma attached to using the left hand, so it didn't seem like a big deal to me. It is possible that in his culture, the taboo against using the left hand is so strong that he can't put aside those feelings when he is in the U.S. even though he knows we don't care. I think he assumed that a Black American would be more sympathetic, would listen to him as a real person, would honor his African culture. This interaction illustrated several issues we've discussed in class. High context meets low context.
Fast food is a very low context activity.
Americans generally expect to order food, get it right away, take it away to eat it. We don t expect conversation, a relationship with the cashier. The clerk was probably from a more high context culture where interactions with other people was more important than efficiency or speed. Probably no one at this restaurant ever thought about how serving food with the left hand would offend some of their employees or customers. Immigrants are pressed to assimilate in many subtle ways in this case cultural control of body movements and interactions with customers.