Just about every guitarist I've ever played with would like a word. And that's exactly what almost all gun collectors remind me of--someone cherishing their toys because they are cool and not because any kind of need. A guitarist no matter how famous does not need 30 or 40 guitars (most don't need more than a couple to play gigs)--not that I care, because people generally don't get killed by strangers with guitars, you just may get exposed to loud wankery that makes you cringe is all.
As far as I'm concerned, self-defense is nothing but an excuse to own toys. But it's legal, and trying to do anything about it is political suicide in exactly one country on earth, so it won't change.
When I felt well enough to cycle regularly I was forever sticking more lights and reflective tape (and electroluminescent wire) over the bike (and getting better tires and upgrading the gears). (I told myself it was for 'safety', to be more visible to motorists, but really it was just that I liked how it looked, to appear like something from Close Encounters of The Third Kind).
I've known people with three or more bicycles of different types. I think the obsessive customising and collecting habit is in no sense unique to gun-nuts.
What I do wonder about, is that for every hobby I've gotten obsessed with collecting and customising things, there's always been an accompanying desire to actually get some use out of the items. I wonder, with gun obsessives, if the things themselves don't somehow cry out to their owners to be brandished and carried and, even, maybe, used. That really struck me in the case of that shooter with the bump-stocks who shot up that music festival (who apparently had a preposterously-vast gun collection). Did they ever establish a motive for that one?