This one is from the part-time job I used to have in a mall. It was the day before Christmas and the mall was packed with shoppers. Almost every bad thing that could go wrong did. Crying babies, lost kids, confused shoppers, unruly teenagers, etc. while the mall managers rode herd on us employees.
We had a Santa setup where kids could come get their pictures made while telling Santa what they wanted for Christmas. The parents caused 99% of all problems and it wasn't unusual for employees to be threatened with bodily harm, lawsuits or even losing their jobs. The rules were plainly posted but parents largely ignored them. Towards the end of the day we were all looking forward to 6pm when Santa would leave and we would begin emptying the mall and locking all the doors.
Mrs. Impatient was at the end of the long line and there was no way she and her brat would get to see Santa before 6pm. She kept yelling at me until I walked over to see what her complaint was.
Mrs. I: We obviously won't get to see Santa because you people don't know how to keep the line moving. If only you had two Santas (!) or some properly trained employees we might get up there before you try to make us leave...
Me (cutting her off): I'm sorry but we are moving people through as fast as they can. It is hard to get pictures made and let the kids talk to Santa...
Mrs. I (cutting me off): Well, I'll just leave and come back next week. What time will Santa be here then?
Me (shocked): Next week is AFTER Christmas. Santa will not be back until November.
Mrs I (mouth open, shocked looked): What do you mean he won't be back until next year?! What about all the kids that don't get to see him before Christmas? Do you want them to wait?!!
Me (thinking): Yeah, all kids want to see Santa AFTER Christmas. And what mall has TWO Santas all dressed up for kids to see.
And yes, Mrs. I. filed a complaint with the managers about me. At least all of us got a laugh over that. ;~)