The latest Bigfoot thing was a scam. Like Reverend BigDumbChimp, I suspected it was going to be some marketing thing or publicity stunt, but it's just a straightforward scam. If I was less specific, I would have gotten $20 off my current DM if he took up the bet. Oh well. Anyway, this post won't be ending with just a link up. Had a short IM conversation with my DM on the topic, and I'll be covering some of the points.
The first thing he brought up were the assumptions necessary to believe they exist: 1) They don't like public places, 2) They live in tribes or families, and 3) They bury their dead. These aren't terribly unreasonable for human-like critters, but I doubt they can explain why Bigfoot photos get blurrier every year despite ever improving technology.
1) Despite the danger us humans pose to animals, we still get them rummaging around our stuff. Why? Food. One thing we're good at here in the US is maintaining our obesity. I have a hard time believing an entire species would have no opportunists whatsoever who'd risk getting caught over the decades.
2) Being in close-knit groups is a useful feature, but there will always be individuals who get lost, separated, or go rogue. Those individuals won't conveniently have the evidence of their existence buried by the tribe.
3) I have a hard time imagining a group of ape-ish people burying their dead in deep graves without using tools. I'm no expert in animal ecology, but I would think scavengers would love shallow graves, exposing bones and such for the world to find after they dig up a meal. If the Bigfeet do use tools, you'd think those 'authentic videos' would show them carrying some. There'd probably be an evidence trail associated with that as well. Of course, you'd expect them to be using our modern objects as tools, which would encourage them to venture into our territory to acquire our fine steel and aluminum objects.
So, even granting my DM his assumptions, I still have a hard time accepting the existence of Bigfoot. If they were out there, you'd think they'd have gotten photographed by now. Lot of people now take surveys of wildlife populations by infrared-triggered cameras. Something as big and warm as an ape would certainly trigger those and snap a clear picture.