Respectfully, I disagree. I come from a family of small town Tennessee folks that hunt, not unlike the Bobo's. Down here, "Shoot him" would never be code for someone is trespassing, go scare them off.
Down here, where neighbors and the police are further away, trespassers are not tolerated. On my property, my home is far enough from the road that anyone who comes to me house was either invited, is lost, or up to no good. If they don't ring the doorbell, I'm going to get my pistol before I step outside, no doubt about it. Even as a light-hearted, or less thoughtful comment between friends, it would be more like "Hey Fred, somebody's sneaking around your garage. Better grab your shotgun". For everyone I know down here, something direct like "That isn't Drew,shoot him" would translate to "something very bad is happening and you need to do whatever is require to stop it right now."
As some one else said yesterday, I think the big unknown for us is whether Karen Bobo is prone to overreact. If she is, then I can better understand Clint not taking her as seriously as the situation called for. If not, then perhaps he was guilty of rationalizing what he saw, as someone else suggested. We may never know.