I think it depends on the deer and where you hunt. In certain suburbs where there are a ton of deer and people, and very few hunters, people don't bother to deer much at all. compare that to a piece of ground that is hunted heavily and the deer run at the very thought of people. Another thing is that deer don't always run when they see people and get spooked, a lot of times they will just freeze or lay low if they don't think you see them, and will let you walk right by. Some are naturally more curious then others, especially young deer (which are often found in freezers by the end of hunting season) which will even walk towards a hunter to try to figure out what in the world that funny looking tree is. I think some people over estimate the effect that humans and predators have to a deer's everyday life, if a deer spooked and ran everytime they smelled a human, or coyote, or bear or whatever, they would be doing nothing but running for their lives 24 hours a day in most places.