Hard to see, but under the hay are 3x 50-lb feed sacks.
I've also hauled a MASSIVE full-grown 250 lb potbelly pig (in a plywood crate). It took three grown men to load it. Another time I carried three grown sheep together in the same crate.
A coworker drives a truck with a trailer hitch on it that's still factory shiny. He's never towed anything in ~4 years.