The Windham Hannaford had no toilet paper on the shelf Thursday. Submitted photo by Linda Young

Faced with the possibility of being stuck at home for days or weeks, Mainers are apparently stocking up on toilet paper like never before.

Shelves normally stocked with rolls of toilet paper were empty Thursday at supermarkets, drugstores and big box stores all over southern Maine as people gathered groceries and supplies ahead of the fast-spreading coronavirus. And it’s not just here. People have emptied stores of toilet paper across the country and in other parts of the world.

Mainers found empty toilet paper shelves Thursday at such stores at Hannaford in Windham and Yarmouth, Walmart in Falmouth and Scarborough, Target in South Portland, and Sam’s Club in Scarborough. The Lowe’s home improvement store in Scarborough was limiting toilet paper purchases to two packages per person.

Why toilet paper? Of all the things we might need if we have to hunker down at home, why have people zeroed in on bath tissue?

“If you run out of sanitizer you can wash your hands with a lot of other things, but with toilet paper people don’t want to use a substitute,” said Lars Perner, a marketing professor at the University of Southern California who studies consumer behavior. “Maybe at one time people would have had old newspapers lying around they could use, but not so much anymore.”

Mainers who spend a lot of time camping and hiking will tell you that tree leaves make a serviceable substitute.

Another reason toilet paper shelves are barren could be the size of the packages, Perner said. They are often sold in bulky packs of 12 or 18 rolls. You don’t have to take too many off the shelf to leave a gaping hole.

And there’s the “social proof” theory, Perner said. People see two restaurants on a street and assume the one with the longer lines has better food. If people see toilet paper selling faster than other staples, they might begin to think it’s more important.

Another reason could be that people are trying to gain a little control over an unprecedented and scary situation by hoarding something they might need, said Erin Carter, a marketing professor at the University of Maine.

“In the U.S., we are a very individualistic and consumption-oriented society. It’s natural for us to think of ourselves first and to look for things we can buy to solve our problems,” Carter wrote in an email to the Press Herald. “Those are not effective solutions in this situation.”

Empty shelves were not helping the stress levels Thursday. Chris Prior of Saco went to Target in South Portland looking for toilet paper but walked to the cash register with an armload of tissues and napkins.

“I’m kind of frustrated, honestly,” said Prior, 29. “I’m suffering because of other people’s actions.”

Priscilla Cote of Old Orchard Beach looked for toilet paper at both Sam’s Club and Walmart in Scarborough. She said she was well-stocked at her home but was trying to find some for elderly friends.

“I can’t believe there’s none anywhere,” said Cote, 70.

Some stores still had toilet paper Thursday. On Facebook, people looking for it were told to check the Dollar Tree near the Maine Mall, the Dollar General in South Portland, as well as Lowe’s and some Shaw’s supermarkets.

Spokespeople for two of Greater Portland’s supermarket chains, Hannaford and Shaw’s, said Thursday that stores without toilet paper will get some soon. Hannaford spokesman Eric Blom said in an email that “every delivery our stores receive includes paper products to replenish what has been sold.”

Charlene Poulin, 42, of Portland had been hoping to buy toilet paper at Target but isn’t that worried that she couldn’t find any. She and her neighbors have a “pact to help each other out” if hard times come.

When Nancy Randolph of Topsham heard her friend, who has two children, was out of toilet paper, she offered to give the family four rolls.

“I have about 20 rolls at home, and there’s only two of us,” said Randolph, 66. “I used to live in Iceland, where you couldn’t always get it, so I always stock up.”

Staff Writer Aimsel Ponti contributed to this story.