I'm sorry, but if someone in street clothes approches me with a badge, I would like a close look at that badge and for the person to behave in a professional, polite manner.
It's not unheard of for bad guys to use fakes to commit crimes.
Finally, UVA girls who shop at that store are of a type (there is a reason I don't go there) I swear, there is no need to draw a gun on those dingbats. The badge and a stern talking to (in a professional manner) would have been enough to make her cry and get their bullying point accross.