Back during the Dynastic era, horses, donkey's, and mules were very valuable for more than labor and meat, but to make armor and weapons. To prevent poaching and to control weapons production, everyone who owned them had to register theirs with the government and the government would collect them so as to prevent people from secretly arming themselves. This made food items made from them something of a luxury good, which thanks in no small part due to the Mao era, remains the case to this day.