In modern times this is the deepest flaw in this logic. Good luck on that battle, it will be a short one I am guessing. Your gun collection is not going to do as much as you hope against drones, missiles, any biological warfare, ect.
I was discussing this with my mom. If you're a billionaire you can pretty much buy whatever you want and still be insanely wealthy, so why would you continue to pursue wealth? It's partly about power, but I think it's a different manifestation of hoarding. Some people hoard objects, some hoard wealth beyond reason. I think there's a bit of mental illness in these cases, just like your standard hoarder.