Perhaps she referred to his ancestry or his mother's sexual preferences or his mother's resemblance to a canine or some derogatory remarks about his children, all prefaced with a "Hey, you broke in line, you jive-a$$...."
A lot of today's youths don't respond well to, "My goodness young lady, that remark was uncalled for."
http://www.knbc.com/slideshow/news/17597175/detail.html
The man even knocks over a little girl with a pink shirt who was with the one he punched. The man is a nut.