Bigfoot is based off fact. A real animal called giganthropithicus lived as little as 300,000 years ago. It's a big forest with plenty of places to hide. who knows if it still exists, but when people like Les Stroud claim to have encountered a Ape in the woods of Alaska, its hard not to believe that a few could still be around.
"Well now, you'll be amazed when I tell you that I'm sure that they exist" - Dr. Jane Goodall