Here are some very good reasons from someone in the business since the '60s.
Originally Posted by Guntrainer
Having been in the gun business since before the '68 GCA, I can tell you I have had numerous loaded firearms pointed at me by "show and tell" permit holders. This ticks me off, and I will generally ask the person to holster or leave.
I assume EVERY FIREARM IS LOADED IF NOT CLEARED IMMEDIATELY, and especially if it comes out of a holster or from concealment.
Recently bought a LC9 and LCR. Will carry those the most. Before that I carried a M&P 9c or a G23 and they will still get carried sometimes. The LC9 is super easy to carry. Still waiting on a belt and pocket holster to carry the LCR. I currently have no holster for it. After pistol matches I usually just carry whatever I used at the match so I have carried a TRP, a XD .45 5", and a G35 a few times. Those are a bit bigger than I usually carry.