> Because 'anti price gouging' laws prevent the price going high enough to make it worth someone going to extreme efforts to upscale production.
While theoretically price gauging is an incentive to increase production, if that's all you're thinking about, you're dealing with a toy model that has little connection to the real world. Toy models can be super compelling and elegant, but that doesn't make them reality. You have to deal with other factors, like
* The influence of parasitic middlemen only looking to flip goods and drive up the price for quick personal profit. In most of these cases, the period of increased demand is so short this is the only effect you'll see, since there's no time to bring new capacity online, but you have all the downsides of increased prices.
* Does price gouging actually direct the scarce resource to where it's needed? Markets often are very irrational, so this can't reasonably be assumed (e.g. during a famine, the market would direct food to the rich and well-fed even if they just were going to waste it on opulent banquets, because they have the money to pay the price).
* People are actually motivated by things other than greed, even though models of behavior are simplified by assuming greed is their only (or main) motivation.
* New production will come online to meet demand, even without price gouging. How much more production would price gouging motivate? Is that production worth the social cost?
* You can't build a sustainable greed-motivated business on building factories to price-gouge. A brand new market entrant is likely to have a pretty poor product compared to established players, and will likely go bankrupt once demand returns to normal. They might not even get their product out the door in time to take advantage of the high prices. It could be a predictable case of "buy high, sell low."
* New techniques will be developed to more efficiently use current production, which may pull the rug out from under anyone who made a heavy capital investment based on the surge demand.
* Etc.
> Without those laws, the price going from $1 per mask to $10 per mask would still be very much affordable for everyone who really needs a mask, and factories who can successfully get decent production underway will earn lots, making it worthwhile to take on the risk of chasing a (possibly short lived) demand.
IIRC, the price gougers drive up the price even higher than $10.