The manager at the time showed me a trick that you just take a pizza box, ram someone in the gut with the point of one corner, then repeat to the face, and the threat would likely be disabled long enough for you to escape.
When I was 21 I worked as a bar tender in a pizza parlor. The manager said that if a fight broke out, get behind the bar, and most of the time they will not follow you.
I took a handgun to work and so did the other bartender.
I wound up calling the police every time a black male ever entered. In math we call that a "one to one correspondence".
