Reekrods are sometimes used for pranks. When Sophie first started attending Foxfire in Keeper of the Lost Cities, a (then-unknown) prodigy had put one into Dame Alina's desk. She threatened punishment when she found out who was responsible. It was later revealed that the person behind this event was Keefe, which was the reason he had lunch detention for most of the book.
Elwin has also used Reekrod as his flavor on the locker DNA strips.
Another time it was referenced was in Lodestar, when Fitz proposed that if someone chose to prank any of the others, they would have to brush their teeth with Reekrod.