Some states, including my home state of Florida do not allow open carry except in very limited situations:
790.053 Open carrying of weapons.—
(1) Except as otherwise provided by law and in subsection (2), it is unlawful for any person to openly carry on or about his or her person any firearm or electric weapon or device. It is not a violation of this section for a person licensed to carry a concealed firearm as provided in s. 790.06(1), and who is lawfully carrying a firearm in a concealed manner, to briefly and openly display the firearm to the ordinary sight of another person, unless the firearm is intentionally displayed in an angry or threatening manner, not in necessary self-defense.
(2) A person may openly carry, for purposes of lawful self-defense:
(a) A self-defense chemical spray.
(b) A nonlethal stun gun or dart-firing stun gun or other nonlethal electric weapon or device that is designed solely for defensive purposes.
Any person violating this section commits a misdemeanor of the second degree, punishable as provided in s. 775.082 or s 775.083.
Even if I could open carry I would not.
First, I can get to my concealed weapon just as quickly as I could if it were in an exposed holster.
Second, I would never intentionally do anything that caused another person to be frightened or uncomfortable. Those who see a person with an exposed firearm have no clue as to the person's character or intent. All they know is the person is armed and therefore dangerous.
Third, If my weapon is concealed I don't have to worry about someone trying to steal it.
In Florida, open carry is illegal even for those with concealed carry permits (with exceptions already cited). I think the laws are reasonable.