Military formations required at least a hundred martial artists to form, so local cities couldn't afford to maintain Imperial Camp Armies— they were too costly.
Not only was there the issue of training so many martial artists, but it also involved exotic beasts; even without forming cavalry units, at least a hundred sets of Sha Qi were required, which local Righteous Courts could simply not afford.
A set of Sha Qi, once used, would inevitably suffer wear and tear, and the military formations had to be practiced regularly, necessitating periodic repairs and replacements.
The two hundred Imperial Camp soldiers in Datong Prefecture City were maintained with great difficulty as a collective effort from all the Righteous Courts in the entire prefecture, and each quarter, additional subsidies for Sha Qi crafting materials had to come from the capital.
Here's a direct comparison, maintaining a single Imperial Camp soldier is more expensive than maintaining ten cavalrymen!
