Quite a few people that I know of. Not without purchase true enough; you have to buy the traps, the guns, the ammo, the fishing tackle, the archery equipment, and the appropriate licenses. Nothing illegal at all though. You buy those things (an investment of about $3000 initially for equipment and licenses the first year and another $ 300-$400 per year thereafter) and sell the furs for about $$35,00 per year if doing it full time and treating it as your only job. I helped a cousin run his part time trapline one season and he made a good chunk of change doing it as a hobby. All perfectly legal. In Alaska the investment is a bit more perhaps but then so is the rreturn.
Thanks; that's none then in reality
Without the trapping aspect (and thus no monetary return) I still know personally of a few dozen people who subsist entirely on hunted deer and trot-lined catfish; again, all perfectly legally.
You're partly right in that it's not "bushcraft." But then it's not "survival" either. It's simply the way they're way of life. And there's no debate involved; it's fact.
You can not survive on protein alone but I guess a bit of homesteading and foraging could provide other necessities
Also seems a bit interesting that when you speak of "my neck of the woods" (the eastern side of the country, particularly the Southeast) you seem to believe that the pre-Columbian Native Americans here were primarily hunter/gatherers. They weren't. They were primarily farmers with established trading routes extending 100s of miles.