The Yanks have a pretty decent fur market, don't forget. Something considered barbaric in Blighty. It's the cash reward that's kept their skills alive, and while they're much more inclined to keep the old ways the cash prize is still what attracts many to what is a painstakingly tedious, and lonely job. Sometimes dangerous too.
Trapping is indeed an ye olde time skill but if you took the approved spring traps back to a time when bows and arrows accounted for most of the world's game you'd be burnt at the stake as a witch!
Gadgetry has it's place. Just remember how we're communicating!