Fellow gun nuts use holsters and don't fire warning shots in the air.... Nor do they lose their temper and shoot at authority figures, or in this case a woman enforcing the rules that literally EVERY gun shop has.
Nobody carries with a 31rd mag in a glock either.
Dude came in looking for trouble. This was probably his general direction for the day, he probably just hesitated at the door.
It's illegal to conceal a gun without a holster in most states, and even though open carry is legal, you can be charged with inciting panic.
Responsible gun owners are aware of this.