I just thought of another! The completely random Rohirrim dude that walks by with a greyhound in
RotK when they're all standing around in Meduseld trying to decide what to do. I've always thought that part hilarious, because they're all serious and "we've won the battle, now we have to decide how to win the war," and this guy just walks by with a dog. Wierd sense of humor, I guess.