Have they stopped trading? Their utter lack of any manufactured goods would lead one to that conclusion.
So they speak various human languages, N/A, various Spanish dialects, and English. They're also capable of telepathically gleaning intentions from a different species, humans.
If they actually traded, they'd be the sharpest darned hagglers in existence. And yet they're satisfied with peanut butter, fruit, and the occasional cigarette lighter. Go figure.
'Tis true, I don't believe bigfoot cross corporeal boundaries. I believe they're flesh and blood. I don't believe any creature, human or not, is capable of reading my mind/intentions. I don't believe any creature can exceed known boundaries of time and space. I don't believe in cat-fights occurring unseen but heard. I don't believe in bigfoot causing one to hear crashing trees nearby.
Problem? I think not. Logic is not a four-letter word. Try it, for a change.
Whether they were more brutish or not, I've always felt Neandertal was much too human in apperance to be associated with Bigfoot, unless perhaps involving a hybridization. I believe their is another species, perhaps yet discovered, that would lend better to Bigfoot.