Sacred Haven of Debauchery

The Hive is a dump; there's nothing logical or humane about it. The Mortuary, on the other hand, is a corporation. No one would want to live in a state that uses your body as cannon fodder after death; everyone would migrate to a good, pleasant kingdom. For military purposes, you can raise spirits and use them as scouts or messengers, without letting them rest, right?

1) They are just cannon fodder in case of war, serving to reduce casualties among the population.
2) They have a demoralizing effect on the enemy, which is quite logical.

They have a demoralizing effect on the soldiers who fight alongside them. To march with a disgusting, bloated corpse, with flies buzzing around it. To build a tent for them so they don't get wet in the rain at night. And what if this corpse is your former comrade or relative?
Zombies go into enemy fire, soldiers nervously smoke and stand around, enjoying the smell of decay. Soldiers storm a Fortress, and there's just a pile of corpses, both decayed and fresh; they won't achieve any military glory, and the general raises a newly killed soldier, who, dropping feces and dripping blood, goes to load stone blocks in the quarry. We're running out of strength; let's replenish the army with fresh corpses; bring the peasants here.

Besides, zombies are of little use as a fighting force. The hassle with all this procedure is greater than the benefit.