My GF always buys backups of everything. When she opens a new bottle of Ketchup, she makes a note and buys its replacement, same with toothpaste, and everything else in the house. Hell, she has an emergency frozen pizza in the freezer. She buys the blue 12 packs of Charmin, 6 rolls go upstairs, 6 rolls go downstairs. Then she buys another 12 pack and stores it in the closet. I made fun of her once so she let it get down to 2 spare rolls, then Covid hit and all the store shelves were emptied of TP. Boy, I showed her nothing bad would happen if she didn't have spare TP on hand. We were down to raiding our hiking packs for toilet paper. I grabbed some spare paper towels from work, but we never needed to use them, thankfully.
Now, we are back up to between 12 to 24 rolls in the house.