Ok well, traumatising experiences:

1) Once when I worked for Sainsbury's we watched a middle aged woman who came in with her husband all over an aisle. I'm not kidding she took a crap in one of the BWS (beers, wines and spirits) aisles. The couple were one of those filthy dirty, smelly comes in in dirty clothes type couples and she honestly didn't seem to notice or care that she was ting everywhere. Even our store cleaners refused to clear it up leaving a duty manager to do it.

2) Again in Sainsbury's I was on a checkout and this customer tried to do a cash snatch when paying which is they'll pay in whatever will keep the till open longest and then try to snatch whatever cash they can and run. I saw this hand come shooting in and in reaction crushed it with the register tray lid by smacking my elbow down so hard in to the till lid that I not only dented it inwards with my elbow but broke the guy's hand and bent the till lid outwards where his hand was.

3) In my first job I had to physically eject a kid for being abusive to customers, it was a computer games store and he was a kurdish child from the owner of the kebab place down the road. He never brought games there he just came in to hang around and be a little bit of a jerk. I physically picked him up and threw him in to the street one day after he refused to leave he then went and got his older brother and father to come up to the store. This resulted in a confrontation between me and my mate who were doing PS2 repairs at the time holding screw drivers because the elder brother had thought it wise to bring a knife along.

Some of the nicer but still "dude thats quite weird" things that happened are stuff like my recent stalker chick who found me on facebook after being served in HMV by me. We later went for a coffee and a chat together, she was actually a nice and attractive girl.

I can probably post more things later.