Lance is in the rear leading the crowd to handle those matters, really not having much time to manage the situation at the front.
But yeah... those knights, if you want to flee, then flee, why burn my stuff?
The Baron considers the territory as his private property, but Lance had long seen these surrounding places as his own.
You burned everything you couldn't take before fleeing; such behavior violated Lance's taboos.
This situation directly led to the core buildings of several Knight's Domains being burned down, including a lot of resources like grain, not to mention killing quite a few people.
Fortunately, after precautions were taken, such situations were suppressed, but the losses already caused couldn't be compensated, still causing many to lose their homes and become refugees.
