Addressing why someone would want to carry a rifle loaded, openly, is the real issue. And speculating that some out of control or simply curious child could reach out and pull the trigger isn't unlikely.
That is exactly why the average reasonable person DOESN'T OC more. There IS a risk, and if everyone did OC with a loaded weapon at all times, then the rate of negligent discharges would go up. As said, the issue already exists for holstered pistol carriers - there are concrete floors and shattered porcelain to point to.
What I would ask is this: have the proponents of OC of rifles gone thru Basic Training? If there is something you learn in the military, it's that having to carry a rifle 24/7 for weeks on end isn't all that fun or such a great idea. It's easy to say it's our absolute right - I get that - it's a PITA to execute, and that's why most people with common sense tend to avoid it.
DUH.
Any number of things can and do happen in a crowd of people carrying long arms, some of which entail losing control of the slung weapon and striking the person behind you between the eyes, getting struck upside the head when your team buddy switches shoulders out of fatigue, getting it hung up by the sling in doorknobs, banging yourself in the head (ah ha, civilian, no helmets!), knees, etc., getting into and out of vehicles, ad infinitum.
You don't just start carrying a slung rifle with no disregard of it's literal impact on the people around you. And if you do, they will quickly inform you in very specific terms about how your cranial function seems to emulate your colon and what it must contain.
In the military, there are very specific conditions and rules about when you carry loaded, precisely to reduce death, reports, and letters to the parents. If trained combat veterans still make mistakes about the rules, how will untrained and mostly posturing wannabes learn other than by mistake?
Don't we do that enough with Driver's Ed? A lot of local courses shut down and it's no longer taught here. I don't think it helped the accident rate one bit.
Now hand a loaded rifle to someone who normally never carries one, ever, other than a few days hunting, or a controlled situation at a range. (Don't try to insert your situation here, I'm trying to make a point.)
Again, the main concern with the CCW crowd is safe carry all day long - holsters that don't let the weapon shift or fall out, don't let the safety disengage, that won't snag the trigger, that cover the trigger adequately. The focus of the draw and getting it on target is, for the beginner, learning not how soon you get your finger on the trigger, but how late you delay it - to prevent shooting yourself. (Score another one why the MSR is actually safer in public than civilian guns.)
Adding a scabbard for rifle carry? At first, I laughed, but on second thought, not a bad idea. It's a "concealment" device, like a day planner tho, and defeats the principle of "Open" carry. So, maybe just a Kydex trigger guard shield would be in order. At least for those who have considerately practiced and have some actual knowledge of how difficult it is to carry a long arm with the public.
That experience should be reflected in the scars around their ears and eyes from all the unprotected front sights that some affect. Score another reason why the military requires certain features - those little ears aren't there to protect the sight blade only, they also protect YOU and YOUR BUDDIES from IT.
Seeing that the average guy doesn't think ahead, it's not the kid pulling the trigger I'm worried about so much as one brushing up against a tactical toothed compensator and having ten stitches in their head from the incident. Glad I won't be the OC proponent who has to deal with an outraged mother in his face and the EMT's, cops, and management pressing their demands.
You wonder why Target asked OC to keep out? Same reason Klingons can't bring in axes and swords OC. Lets take a breath and consider being considerate to the rest of the public - which is why the poll is right on the subject of our Rights, but actual practice is that we recognize the unintended consequences. Do unto others as you would have them do unto you.
Guns slipping off shoulders and banging heads, adult or child, are not welcome, same as shooting the toilet in the men's room.