Not at camp, but on the way home from one:
One time my mrs was super stroppy as they forgot to put sugar in her takeaway latte (we were already on the move before she had a taste). Her being stroppy just makes me laugh which proceeded to piss her off even more.
I just couldn't stop laughing so she grabbed my hot chocolate, wound down her window and proceeded to throw it out, only it was still full and she squeezed it a bit too hard and most of it ended up on the inside of her side of the windscreen and on her door.
That just got me laughing harder, so much so that I got a stitch.
A short while later I did the gentlemanly thing, pulled over, cleaned up her side of the car and got her some sugar out of the camper trailer so she could then enjoy her latte.