I hate it when customers think it's funny to scan their own items.
I had this guy come in one time doing this. I seriously think he did it to scam me and get free stuff.
He walks up to my register with a crapload of items, mostly candy bars. I'm talking about probably 15-20 various small items of candy. Something that would be easy to get messed up on.
He makes some small talk with me, flashing his bright yellow smile, and proceeds to pick up one of his items, reach over, and scan it with my scanner.
Once he did this, he stood back, fake smiling and softly laughing, probably trying to gauge my reaction. I played along, fakely laughing as well.
Well I guess he thought it was okay, because he started to scan more of his items into the register. Back then, I was too polite to say anything and thought I would get yelled at for 'being mean to a customer', so I just stood there, quietly supervising.
Well this guy quickly picked up speed, because soon I saw hands and candy flying everywhere, and the occasional scanner beep going off.
I wasn't sure what happened, it had all gone too fast. Next thing I know, I'm bagging his items up while he's handing me his money and telling me to keep the change.
He quickly said goodbye and got out of there. I look at the register and see that his total was $4.52. He had handed me $5 and told me to keep the change. There was no way all the shit he bought only came to $4.52. That bitch had scammed me.
So now, when people try to scan their own items, I get pissed. It is not your job to do my job. You are not making it easier on me by scanning your items. And if you happen to scan it twice by accident, then that's your fault and you're paying for it.