During the 2-month lockdown a year ago, I would purchase 4 frozen pizzas at a time when I had a chance to buy them, because I was so upset that I could not buy one when I wanted a single one during the 2 previous weeks, because of hoarders who had been faster than me.
People think of toilet papers, but it is not just that. Pasta, rice, flour, yeast, plenty of useful things went missing due to hoarders during lockdown. Thankfully, I don't eat meat, because there was no meat at the supermarkets. Fish was also hard to find in the frozen shelves of the supermarkets. I am not a big fish eater either, so it was fine for me as well, but you get the idea: if you don't hoard a tiny bit, you get increasingly frustrated because hoarders will hoard, and you will have to wait for weeks before you get the chance to have what you want.