"No one did anything"

I was in line at a fast food restaurant where a woman approached me from behind and punched me in the shoulder. She started yelling obscenities and asked me where I came from. I ran behind the front counter where the cashier let me stay to wait for the woman yelling at me to leave. Despite there being at least 10 other people in the store, no one did anything and we all waited for the woman to leave who was still yelling anti-Asian slurs at me. The cashier told me that the woman was a regular, but it still bothered me that no one did anything to intervene.