Many people around the world have been racing to stores to stockpile goods like toilet paper and pasta as coronavirus (aka COVID-19) cases continue to rise. (As of Friday, the global death toll for coronavirus neared 5,000, according to data compiled by Johns Hopkins University.)

Whether you've been personally touched by coronavirus or not, it is well-advised to at least be prepared with the essentials.

"Store a two-week supply of water and food," the U.S. Department of Homeland Security's emergencies and disaster prep site, ready.gov, suggests.

The site also advises periodic checks of any prescription drugs to ensure a continuous supply and a refill of any nonprescription drugs like pain relievers, cough, and cold medicines. Additionally, the American Red Cross recommends keeping an at-home first aid kit to treat common injuries, including cuts, scrapes, swelling, sprains, strains and more.

None of that includes a 30-pack of Charmin.

"Right now, people are doing incredibly silly things," Regina Phelps, a pandemic planner and crisis management expert, tells CNBC Make It.

That's understandable — in her two decades as a pandemic planner, Phelps has learned that when people or companies don't develop a plan about what they actually need in advance, the "natural kind of response" is to buy things they don't need and will end up never using.

But it can get expensive, and it's unnecessary.

Phelps, the founder of Emergency Management & Safety Solutions in San Francisco, where she advises companies like Whole Foods, Nike and Starbucks on crisis management plans, including possible pandemics, says these are some of the things she sees people waste money on.