I guess it went with the territory, Mountain Men being bigger than life and all.  Not that they were the only story tellers who inflated the truth.  However, it does remain a fact that these tough characters had a almost universal propensity to embroider their descriptions of life in the wilderness with what can only be described, in the final analysis, as full blown and unadulterated lies.  Because of this reputation, one that followed them for all their lives, many amazing but true stories were met with derision and ridicule.  For an example, I give you John Colter who explored the area later to be known as Yellowstone Park.  His vivid description of what he actually saw and experienced scandalized most Easterners who could not imagine such things!  Boiling mud and geezers?  Bah! Humbug!