If they shouldn’t carry a firearm yet….
You may seriously want to consider looking into some of the modern less-lethal options. After spending many years on the firing line, in professional situations and in casual environments, I’ve seen plenty of people pushed into firing guns that they did not feel comfortable shooting and even a handful of people that probable shouldn’t be on the firing line. I believe most of our population can handle some level of firearm proficiency, but I strongly recommend against pushing carrying firearms for novice gun owners. There are always variables we can argue about, but if I knew someone that was working late nights as a waitress or working at a bar, I would not pressure them to carry a gun if they did not have the training to use it.
The point of this discussion is a firearm should be a deterent, pulling a gun on a robber doesn’t give you the right to shoot them, but it will stop a crime, if you’re dealing with a weak individual that couldn’t handle the stress of the situation, the gun they are carrying may end up being used against them. One point I constantly push when discussiong CCW is that firearms, especially handguns, are not going to stop someone in their tracks. They may bleed all over you and use the last round in your chamber on YOU if you aren’t prepared to deal with it. There are many less-lethal weapons like Tasers and Kimber Guardian Angels that take very little training and may actually be more effective and have fewer legal liabilities if used.