The energy crystals contained energy that could be absorbed by the lord himself.
This was the main way for the desolate hunters to improve themselves!
Usually, the desolate hunters were much stronger than the lords because they did not have a territory. They had to fight together with the soldiers and increase their strength by eating demonic meat and absorbing energy crystals.
However, for the lord, no one would choose to use energy crystals to improve themselves.
Energy crystals were an important resource to improve the territory's strength. To the lord, nothing was more important than improving the overall strength of the territory.
Moreover, with the recruitment pool and the territory, it was naturally a priority to improve the combat strength of the troops. They did not have to participate in the battle.