Very well then:
1. Every living organism, from Elephants to bacteria, leaves it own ecological impact on the environment. EX: a new predator is introduced into a large area full of deer. As time goes on, the deer population will start to decrease, due to the predator consuming them. Bigfoot, however, does not leave any ecological impact on its environment. There is no decrease in deer, elk, bear, plants, etc population, which you would expect if there was a breeding population of monstrous apes, which in reality there is no such thing.
But would wandering small hunter/ gatherer groups leave that much impact in the far northern reaches of Canada. Did the Indians deplete the buffalo?
2. Lack of remains- Every Animal, no matter how rare, has to leave remains behind. Scientists have no trouble finding a new species of insect in the remote, unaccessible areas of the Congo, yet no one can seem to find a population of hairy titans living in such close perimeters to people. The fact that nearly all of NA has been mapped and developed, yet not one finding of any large ape remains, makes the likelyhood of bigfoot plummet extremely low.
But if they buried, burned or even ate their dead, that would make the likelhood of finding remains of small tribes slim
3. Lack of tools- If bigfoot has evaded man for all of these centuries, you would certainly expect tools and culture from such a smart species. The fact that bigfoot is never found, yet is described as smart as a bag of dirt, does not support consistency for it being a real species.
Maybe for some reason they are terrified out of their wits of man and avoid him at all costs. Do apes have tools and "cities"? Its not hard to elude man. Its his dogs that are hard to hide from. Ask Mr Cougar
4. Every mammal, when giving birth, would be experiencing so much pain, which would make them scream their heads off. A sasquatch would require a huge voicebox, and if ever in a painful situation, its voice would certainly be heard for miles and miles.
Aw come on
5. Not all forests remote- Even the Dark, mysterious forests of the PNW are surveyed and mapped to death. Wildlife biologists and park rangers do travel great distances and cover so much land that any large species would be found by now.
Valid point - for the PNW, but not the Yukon NWT and the area around Hudson Bay. Siberia as well
6. Why so few sightings?- If this thing is real, it has to have an MVP (Minimum viable population) of around 4000. If this were the case, people would be running into these things daily, not once in every blue moon.
See above answer
7. No consistent behavior- No one has ever reported seeing a bigfoot give birth, mate, or fight with each other, all of which you would see in a real population of a REAL species.
8. Bigfoot is reported in all 50 states, yet not one sighting has ever lead to good evidence.
Most of the sightings, if not all, in the lower 48 are hoaxes. They don't count. And really? They have been reported in Hawaii??
9. Where the tracks lead to- A couple 1000 of these Hairy giants would certainly leave trackways behind. Don't you think that at least one trackway would lead you to your grand prize?
Again it depends on how remote the place is. It would be difficult to find tracks in, say the Northwest Territories becuse the only people who visit there are fishermen not looking to bag a bigfoot and possible Bigfoot hoaxers. No scientists looking for Bigfoot as far as I know
All that being said. Bigfoot will have to remain a myth until definitive scientific proof is shown.