I don't have a problem with guns or people who want to own as many guns as they can afford within the laws of their state. That being said...
If you're carrying around a semi-automatic rifle or a semi-automatic assault riffle with the sole purpose of showing people that you can legally do so and intentionally or unintentionally intimidating those going about their business in a public area... You are a jackass. You are someone who reads the 2nd amendment without acknowledging the personal responsibility and mutual respect for the rights of others that comes with gun ownership.
Liberty and Freedom, with some pragmatic common sense.
What was the need, what was the purpose of bringing the gun? Did he feel threatened? Was his life or personal property in danger? No, not while he was carrying the gun, of course. The point is, the other people passing him or noticing him, they don't know him or what he's up to--for a brief moment he was walking on their liberty and freedom to make his little point.
Some libertarians see this--they get that guns make some people uncomfortable and they are respectful of that. They understand that the liberty and freedom comes with a mutual respect for others. Are you one of those libertarians?