IF Bigfoot is a multi-dimensional being, then who knows. It could also explain the lack of any remnant discoveries anywhere, that I am aware of, to date.
If Bigfoot is the remains of the original Homosapien (prior to "alien" genetic alterations that produced us as we are today), as per another growing theory out there, then they must be burying their dead somehow and somewhere. I do not believe that Bigfoot would be cremating their dead, so burying seems a logical action based on the lack of physical discoveries.