When crisis strikes, leaders often call for sacrifice. In the aftermath of Hurricane Harvey and in these days before Hurricane Irma churns ashore in Florida, we've seen innumerable Americans volunteer, sacrifice and even risk their lives to help others.

It might be too easy to contrast that generous spirit with the strict practices of major air carriers. But airlines make it pretty much irresistible.

When Florida Gov. Rick Scott advised people who may be in the path of Hurricane Irma to "leave now," it posed a challenge for those who tried to fly out of airports in southern Florida. Many found the price of a single seat to fly, say, just from Miami to New York could cost more than $3,000. For a family of four, that is as much as their annual budget for groceries.

Complaints burst onto social media platforms: A man named Joseph Pep Nodarse tweeted, "Totally unacceptable, a $358 flight from Miami to NYC went up to $3578. Why should expect anything decent from these airlines???" That was followed by an abbreviated expletive in front of "RATS!" in all caps.

State laws prohibit price gouging during a state of emergency. Air carriers are regulated by federal agencies. But were the airlines price gouging with those ticket prices? I'm not sure if the answer is "no" or "no more than usual."

Seth Kaplan, managing partner at Airline Weekly, explained to several news organizations that algorithms in the software of major airlines monitor supply and demand, then lower or raise prices accordingly — within seconds. "This is what happens when thousand of people want to leave a place all at once," he told The Verge. When people want to — or in this case, need to — leave immediately, prices can rise alarmingly.

By the way: I've become convinced that "algorithms" must be a Latin phrase for "Don't blame us, it's the software."

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