Because again they don’t attribute their behavior to their own volition. The fact their hunting is a behavioral response initiated by the need for food. The mistake we make in our modern thinking is that, when we think about our behavior, we think like, “I’m hungry, so I’m going to decide to eat,” when the behavior is more accurately explained as “eating behavior is initiated by the need to eat.” Hunting is a system of behaviors, a system that self-evolved over time. While it includes humans, the system is consists of the environment, the hunted animals, and the collection of humans involved that all act interdependently to form what we call a hunt. While we perceive the people, the animals, and the environment as distinct parts, that’s just an illusion created by our brains.
So, my impression is that the hunters during this time had yet to develop the perspective we have, meaning they didn’t see themselves at the center of their decision-making. Their hunting behaviors are initiated and executed, outside their own free well, by 1) their hunger, which they have no control over, 2) the constraints of their bodies, like their strength, 3) the constraints of the environment that determine where they can go and what they can do, and 4) the behavior of the hunted animals. None of these things they can attribute to their own free will. The error that our brains make automatically is that we perceives ourselves at the center of this system. When I watch myself do something, I unconsciously think, “I did that because I decided to,” when in fact I did that because the interactions between my brain and the environment produced a semi-predictable reaction that “I” was not involved in creating. We assume we are the centers of what we do and what happens to us, when in fact there is no center and this interdependent system carries out on its own. We are just along for the ride, and in this sense the Reindeer People are right.