We fish, because that's where our past generations obtained their food.
It's like "why does siting in front of a camp fire seem so natural" and comforting, as it's been ingrained into our DNA since caveman days.
Just because we fish, doesn't mean we kill..........you can catch and release all day long with a barbless hook.
try hunting with a barbless bullet.?
Something is special about fly fishing, to present a fly to a trout, play the fish, then release.