The reason some people open carry is to aggravate the cops and other folks who don't like it. More than most gun-rights issues this one brings out the immature side of some gun owners who, like rebellious teenagers, are doing it simply because they can.
In this case, our man did it so he could secretly film the cops making fools of themselves, which they certainly did. Now, is that a big victory for the gun-rights movement. I think not.