You don't really see animals running for hours in the wild. They sprint to hunt or survive, then they walk.
So you don't tend to see animals running for hours because that's a human speciality (among predators), and it's part of why we've been so successful as a species, despite our physical weakness compared to other predators.
And the reason people need technique bootcamp is they're not physically active anymore. They have muscular imbalances that need direct attention to correct.