Yes customers can be a bitch.

My mom worked in a video store. She put up with some rude ones, however one day she was lucky my brother happen to come into the store. Some beligerant customer dude was giving her crap about some charge on a late video, and my brother while in the store heard the commotion and walked over. The customer actually lunged across the counter top at my mom, she backed up so he could not grab her. Well my brother intervened and told him you ever do that to my mom again I will flatten your ass (my brother is 6ft 1 and 250 lbs). The dude did not say a word and left, ha ha!!!

Thank GOD my brother was there!