It might be better if you are not wishing to promote the Second Amendment.
He may have exercised bad judgement.
Carrying a firearm concealed supports the Second Amendment, but it also says the carrier is ashamed or afraid of carrying openly.
Opponents of the Second Amendment dislike open carriers more than they dislike concealed carriers, because open carry proudly proclaims support of the Second Amendment.
It is an individual choice.
The Supreme Court has implied that open carry may be protected, while concealed carry may not be. That is what the Ninth Circuit has ruled.
I strongly disagree.
In any situation involving a mass shooting by a criminal or terrorist, the first one that he will target is someone openly carrying a firearm. Carrying a concealed firearm says that the carrier wants to be able to take out a shooter before the shooter knows that he is armed.
Concealed carry also protects those who are not carrying. Where concealed carry is permitted and encouraged, criminals and terrorists have no way to tell if anyone is carrying or not. As a general rule, if you intend to commit a crime or a terrorist act with a firearm, you are not going to choose a location where your intended victims may be able to fire back. This is why mass shooters almost always target so called "gun free zones."
You are inconsiderate toward others. It is just that simple. Surly you can’t tell me with a straight face that going into a retail store wearing armor, packing an AR15, and making a video of yourself on patrol is a responsible citizen’s exercise of rights. If you think this is normal, you are a poster child for the Red Flag laws.