You would think that the demand for their products would be incentive for them to make more of it.
Am I missing something here?
There isn't a single company in the world, past present or future, that can scale supply to meet demand the way you seem to think they should be able to. Its not a simple function of turn the machines up to 11 and make more product, they need raw materials (these raw materials by the way, arent just used to make gun powder so they are competing with other industries and changing prices to get what they need), they need more people to set up/run/clean/re-cycle the machines, warehouse space, shipping infrastructure, etc etc etc... those things require massive capital outlays that wont necessarily pay off in the long run once supply stabilizes. Never mind the whole aspect of their industry being extremely highly regulated which adds a significant time factor to all the steps required to scale up output.
The whole "bUt ThEy ARe lOsINg cUStOmeRs!" thing always confuses me. Yes, they may lose YOU as a customer, but No, they arent losing customers on an aggregate level, they are literally selling 100% of everything they can make right now, so the fact that you might switch to Alliant or someone else doesn't really bother them because there's hundreds of more people who will take your place in line waiting. There's no loyalty in the equation here... product out = dollars in. Its the same thing that always gets me when people complain about firearms companies with high demand product wont offer layaway , financing, discounts, T&E examples, etc etc etc... why would they? All of those things create risk or eat into margin on something that they could literally sell every single unit at MSRP or even marked up if they wanted to. Economics doesnt care about your feelings. It's not just firearms... go to a Ford dealership and try and buy a new Raptor, or a GT, or go to Chevy and try and buy a C8. Sure... sign a purchase order for full marked up price and take your spot in line with the thousands of other people. You storm out of the dealership angry and 5 other people walk in behind you who want the same thing.
Think about it, I know everyone on this forum likes to believe that cartridges like the 6.5 Creedmoor, the PRC twins, the move to large overbore magnums for ELR hunting etc are just passing fads, but they have brought new shooters into the sport in droves. This means more demand for factory ammo, and more demand for handloading components. To my original point, they are scaling supply, but if demand is growing at 10x what they can reasonably scale up supply, its going to be stocked out.
It's not exactly impossible, I was able to buy 8lbs of H1000 a few months ago, and it stayed in stock for almost a week after I placed my order, there's product out there if you are patient and willing to look for it.
So yeah... you are missing quite a lot, and showing a fair amount of ignorance in the process.