How many people on a survey would respond positively that they'd hoard goods at the expense of others?

Very few. On surveys, 78 percent of Americans disagree with even 'no victim' greed like being paid more than someone else to do the same job and yet if there is one thing that California's reaction to 335 cases of COVID-19 in a state of 40,000,000 has shown, it is that at the first sign of trouble it's all about greed. And it makes no difference if you are a CEO or an employee, a Democrat or, in California, even more of a Democrat. Nearly everyone is doing it.

There has been no disruption to any supply chains, Yellowstone did not erupt, an earthquake did not separate the state from the rest of the country, all it took was .000008 of people getting a disease in order for a state that regards itself as a bastion of progressivism and equality to revert to hard-core free market conservatism, really not much different than that guy who bought up 17,000 bottles of Purell. Store shelves have been vaporized of basic goods and the rationale is that people buying a bedroom full of toilet paper are doing a public service.

It is hard to rationalize that behavior as anything but selfish. The usual deflection for why people in California are more anti-vaccine, more anti-everything in science, than the rest of the country is that they don't claim to be that way on surveys. Few claim to be anti-science on surveys, yet in actual behavior they are. Part of the reason why I wanted to write 2012's Science Left Behind was that some schools on the coast had only a 27 percent vaccination rate, yet on surveys coastal progressives did not admit to being more anti-vaccine, even though Republican states like Alabama and Mississippi had negligible vaccine denial. CDC data showed the three states on the continental west coast locked down the top three spots in vaccine denial while saying on surveys they did nothing of the kind. 

Yes, our California Governor Newsom is part of the panic problem. He is promoting hysteria that isn't based on evidence, declaring it a criminal offense (no, really) to leave your house in coastal counties totaling 7,000,000 people unless the government deems your movement "essential", but that is no reason for the rest of the state to behave like Doomsday Preppers.

This is not clinical OCD hoarding, people are just acting like it

The Hoarding Rating Scale (Tolin, et al., Psychiatry Research, 178, 147-152.) asks questions like to what extent you buy more things than you need or can use. On that one question alone many Californians are over halfway to the 14 points indicating there should be a clinical diagnosis. I am not saying that for dramatic effect, I do not trivialize OCD behavior. This is not OCD, it is greedy behavior depriving the poor and senior citizens on fixed incomes of essentials so 'me first' types can have enough to last until July.

Yet surveys show they do not admit to being greedy any more than they admitted to being anti-vaccine - despite their behavior. Anti-science activists mask their denial in language about choice and 'needs more testing' and the precautionary principle. Along with declaring Republicans more racist in offhand bigoted fashion, it is common in California to claim Republicans are more greedy. And on survey questions like "I think it's morally wrong that rich children inherit a lot of money while poor children inherit nothing", liberals overwhelmingly agree. Except in actual behavior people in California embrace a far better life for their children than those kids in lower income families who only have money to shop every two weeks and can't just stock up before supplies run out.

If a survey asked 'in a disaster would you buy up months of reserves for your family knowing it will penalize your neighbors?' how would you respond? Behavior shows we know how most will act. Because the behavior is happening nationwide in a real-time experiment with millions and millions of people.

Women are no better than men on this one. While on surveys, political beliefs are linked to different attitudes about behaviors while gender is not, when it comes to actual behavior it is all the same.

Surveys are surveys and acts are acts. At the first sign of trouble, most people get greedy. Which says a lot of our beliefs about how much better we are than the other side(s) when it comes to politics is just a veil we wear to feel better about ourselves. 

But we can be ethical human beings too, we are not simple animals. It is time to act like it.