Yes, but there are limitations.
Factories/production facilities/workers can only put out so many widgets in a day. I imagine that most every shooting-related company out there would love to sell more widgets, and make that extra money, but they are at their limits already.
The "factories" didn't overbuild (sound reasoning in any business), and were likely running near capacity already for efficiency and return on investment purposes.
Now there is an increased demand.
Factories are reluctant to expand, as this cycle will eventually run it's course, and then they have excess capacity that is not needed, thus not making them any money. Besides, ramping up more production ability takes time. The current boom cycle may very well go bust before they could physically expand.
Add in demand for raw materials from developing countries (China.....), and a hoarding mentality on the part of shooters who grab every pound of powder at the gun shop and every 22 LR round to hit the Wal-Mart shelf, and you find yourself in the situation that we are currently experiencing.