I was playing a while ago, and my guards from the barracks were leaving the town to go kill the monsters buildings outside. At first it was annoying, since they'd sometimes get themselves killed outside the village, but in the late-game I liked that they'd go out to destroy the monsters.
I don't know if this was caused by a bug, but having two types of barracks in the game might not be a bad idea.
Defensive - To prevent the monsters from slaughtering everybody in the village.
Offensive - To conquer the world. Could be a good way to burn off excess villagers.