Increased cost disincentivizes hoarding and incentivizes everyone to conserve, meaning there's more to go around.

If there are people who literally can't afford to buy hand sanitizer then that's a problem which needs to be dealt with separately, through non-market means. Artificially keeping cost low for everyone without increasing supply isn't the solution; all that does is create a situation where hand santisier is sold out everywhere and no one can get any. It also reduces the incentive for companies that manufacture hand sanitizer to increase their supply, and reduces the amount of capital they have available to increase production in the first place.

"Literally can't afford" is a very murky line though. What if they can afford it but only if they forgo some other necessity? Does that solve the problem perhaps?

My office, which sent everybody home, also got hand sanitizer for every conference room. The same conference rooms that nobody is using. It's a colossal waste. And I work for a FAANG. It would have been good if they had had to pay an inflated price for hand sanitizer and has therefore reconsidered and not contributed to the shortage.