Guns are supposed to be tools right?
I have some guns that make me feel exactly as you have said. Like my glock, I could care less what happens to it.
Other guns are different. Some are functioning art. Like a gorgeous blued colt revolver, browning high power or a beautifully crafted, hand-built 1911. Do I own anything like that? No, but I can see why someone would want to. I have a couple of nice 1911's that I don't like to see get damaged. Sure, some wear is ok...but not nicks and dings. It isn't the end of the world, but I'd rather not see a big ol' ding in the slide where I dropped it on concrete or something.
This probably stems from repairing new damaged furniture at a furniture store in high school, but I really, really, really , really, really, really, really hate scratching wood. If my 1911 grips or rifles stocks get scratched, I cringe. I'll eventually replace or refinish them. I have an old Marlin 22 that my dad discovered in a closet that I am currently refinishing. The gun might be worth $100, but it is accurate and deserves a scratch free stock. I guess that's just me. I also have an old stephens 12 gauge that my dad and I refinished. It's a hard kicking single-shot 12 gauge that is likely worthless, too. But I want it pristine just the way dad and I refinished the stocks. I can pass it on to my son when he gets older and he can beat on it, then we'll refinish it when he gets older and no longer needs it except for sentimental reasons.
If I need a rifle or a shotgun that will be tossed about in the truck or venture through thick brush...I'll fit a composite stock on it. For some reason, plastic makes something look very utilitarian to me and then I don't care about the scratch, nicks or dings.
Edit:: I also love old race-cars. They are built to be run hard, beaten within an inch of their life and retired when no longer useful. Still, you gotta admit that it is nice seeing "restored from what's left yet functional and %100 authentic" Trans-Am era race cars, Ferrari Le-mans cars or anything else that may tickle your fancy at museums and exhibits. Same with planes...that non-functioning, record speed setting blackbird at Wright-Patterson AFB museum in Dayton, Ohio sure felt like more than a tool as it was designed once I put my hand on it. Some things can bring history to life once you get to feel them in your hand, unlike non-functioning art, like paintings or sculptures not meant to be touched by human hands. We're guys. That's how most of us work. Even my young sons don't dig history very much. But once I take them to a coastal ghost town full of colonial era building ruins, or a battleship tour by the beach where they get to touch historical items...it suddenly becomes "cool" and they "wonder what it must have been like back then."