They don't have trained eyes to see movement; they don't see a partial deer; they don't see movement from a squirrel; they don't see a coyote moving silently through an area; they don't study small areas, really small areas.
Their eyes are trained for urban life; not hunting lands.

And in modern life, some are trained to use an iphone, and not just look for movement. Minutes, hours, just looking for movement.