StephMK said:
I would be willing to bet there is more to the story than reported. Since that clip shows the non matching family using racist language, that's probably where the original disagreement started and we are missing some details about what happened/what was said during being passed in line, etc.
To me, what was said is irrelevant. I don't care how hateful someone gets - I don't care what slur they call me. I have the choice to walk away. The first person to get physical is at fault. Even if someone is screaming in your face, a mature adult with any sense of self control walks away, finds a CM, security, etc.