Several of the qualified purchasers don't carry guns in their line of work, ie EMTs. When I was a kid his dad sold to everyone and then had the discounts for LEO, sorta like Keisler's down south.
I can introduce you to several EMTs and Paramedics that CC while working. A few of them have been shot at/robbed for the drugs on their truck. There are some places in Fort Wayne TRAA (local Ambulance Company)will NOT let their people go into until Police have secured the area because of this. Now I have never heard of a Fireman carrying at work but I won't say there are none out there.