Don't fall into the "need" logic trap. It is the province of the banners.
I am about your age and retired, so my earning days are behind me. On the plus side, a lifetime supply ain't that much any more. But I bought it cheap with the understanding that real and imagined shortages, price hikes, punitive taxes, legislation against evil bullets or the evil raw material lead could seriously damage price and availability. My only surprise was how soon it happened.
Extra ammo is a good inflation resistant store of wealth and good trading or sale stock in lean times. Frankly, I can see no reason not to buy substantial stores of good ammo when the prices are reasonable. Stocking up now would be a bad strategy other than absolute short-term need. But over-supply in general makes sense to me from a number of perspectives. I also think it promotes the cause of liberty for this much ammo to be in private hands and past the last gate of government control. The banners have unwittingly created the very thing they sought to prevent - more ammo "out there". Or as they would say "on the streets", though I have looked and never seen any ammo there.
In terms of demographics I may have quite a bit in common with you.
My deep supply exists because of longevity. Even if there was no conspiracy at work, inflation is eating away at the capacities of each of us in terms of how easily we may be able to purchase ammunition at some point in the future. I want to be able to hunt, plink, or defend myself not just today but 20 years in the future (if I'm still around). I want my children and their children to be able to also.
My supply does not exist because of some vision or prediction of an Alamo or Waco event. It is to have enough over the long run.