I have never flown to a hunt. I was checking into this a few months ago. Delta will allow me (FF) to have 70# bags, 2 for free. The third bag, also 70# is only $25 and even a fourth is only $75.
However, when I'm hunting out west I'm usually doing so with 1-2 friends and/or my son. None of them can get these baggage rates and it gets expensive fast. I generally truckpool.
However, I have been on hunts when a member of the party flew in and out. Last time was an antelope hunt. We picked up the hunter (my friend's son), he hunted, bow-killed an antelope, and we brought it and two others, home for him.