Bully at work ?

I was finishing up my shift at the part time tonight when the loud mouth employee (35male) came around saying offense things to other coworkers. He said to an Asian-American "man Jet Li's cousin get out the way" and called another kid fat and a punk for talking under his breath. This sh*t made me uncomfortable and I'm ashamed I didn't say anything for them. I'm not a fighter or anything but it made me want to fight win or lose. I just can't understand why grown men are like this. What should I have done? Should your boy go get boxing lessons?