1. I believe the purpose of pushing Open Carry by some is to show the 'bad guys' out there that the US not a playground to commit crime.
1b. Why? their job is to enforce laws, not go around and check every open carrier. That's like asking cops to waste their time checking wood studs in every house to see if their up to code.
2. Whats the difference? Open or closed carry, you think if I have my gun exposed I will be different. LEO/Military also have the exposure to some sick stuff in this world, they are more prone to getting psychological disorders from that, those tests make sure it doesn't become an issue.
3. The point is yelling fire in a crowd will cause panic. I have never seen someone open carry create a panic. Even the little news stories about how 'concerned mom' called the cops about a open carry guy in a mall so they showed up doesn't mean anything. If the mom wasn't so uptight and knew the laws better it wouldn't even have been an issue. The shooting in connecticut also fueled that concerned mom because it was a few weeks after it.