There is however, I believe, a fast growing interest in our sport/ hobby, which is good IMO.
I think that is a lot of it. We have a LOT of soldiers and former soldiers from 10 years of dual wars in the population now. Many of them like guns. And I think this current generations of 15-35 year olds has a revived interest in guns.
Look at all the gun programs on cable TV these days. Look at the ever increasing number of conceal carry permits. I think most of this is just due to a successful effort on all our parts to get more young people involved. They've discovered the mainstream PC media is full of crap about guns and they enjoy shooting and owning them for defense as well.
The other factor is today's shooters are not like those in the 1960s shooting a box or two per year. Many guys are going out and running through several boxes per range trip. I still have some of my Dad's ammo from the 1960s--he never shot it all and he rarely had more than four boxes any caliber. Same with firearms. I grew up in a house with more guns than typical, but it was one rifle and shotgun per hunter, and a couple of .22s. Nowadays many of like to have a variety of guns and calibers, and even some redundancy (per Murphy).
I'll bet the number of guns bought and rounds of ammo shot per year, per shooter, is many times today what it was thirty years ago or even ten years ago. Finally, prepping is becoming more popular not just for stocking up on guns but tools, supplies, everything.
We should be thrilled there are so many more shooters today. Makes supplying that demand more of a problem, but what a nice problem to have.