The Kel-Tec doesn't have a safety.. no more than a pocket sized revolver does. Doesn't need one. The trigger pull is long,.. not particularly light. It won't fire unintentionally. The firing pin is not under tension as it might be with older style semiautos, so the weapon is as safe in that carry condition as is a revolver.
.... that being said, we could start another thread on firearm stupidity. I've seen plenty...
But I'd have no problems carrying the Kel-Tec loaded and chambered in my pocket. One value a pocket holster has, though, is protection from dust bunnies, lint, and pocket debris. Without a pocket holster my EDC carry (S&W M342) picks up a great deal of lint.

I do have one of those Daytimer Organizers with a built in holster. I stopped using it. It represented a way to drop/loose all of my EDC stuff at once. It was also too visable a target for a rip-off (and I lost a S&W M60 that way) Now I use my pockets.

Although I hate to admit it, (it is so UN-Macho)the most frequently used part of my EDC gear is my Fisher Bullet Pen. I wish I could say it was my Combat Kukri, my Siltarp, my paracord,..etc. But no. It is the lowly pen!