what does U.S. law say about selling,
giving away, or trading hunted meat?  Does anyone know?

I spoke with a co-worker who hunts yesterday.  He informed me that it is illegal
to hunt and then sell what you've brought back.    However, participating in a
hunting club, he does trade his kills (for smoked items) and he is generous with
his catches.

He recommended that if I'm interested in game meat to seek out places where it's
processed at the request of hunters.

He also informed me to not expect to find "wild" game meat at legal resellers.