Gosh I have so many. For one, used pads are left quite frequently in our fitting rooms. Lovely.
A couple years ago there was a group of 5 teenagers in the family room with about 60 pairs of jeans. The FR operator was on lunch, so they were able to sneak right in. They stayed for an hour, and when they left they left behind all 60 pairs of jeans inside out all in a pile on the floor. The FR operator came back and her and I started picking up each pair of jeans folding them back properly. Then, when we finally reached the bottom there was a big pile of POOP. These scum trashy teenagers POOPED under all of it. I absolutely hate them to this day.