Yesterday, at the Pak'nSave supermarket in the Auckland suburb of Royal Oak, queues could be seen reaching out into the car park.
And this morning Pak'nSave, New World, Four Square, Raeward Fresh, Countdown, Fresh Choice and Super Value came together to issue a plea.
"We understand this is a very uncertain time for our country," they wrote in a message to New Zealand, taken out on a full-page of the Herald this morning.
They asked Kiwis to shop as they normally would, to be considerate of other shoppers and to avoid stockpiling.
"By all means pick up a couple of extra things in your shop, but there is no need to stock up for weeks in advance," they wrote.
In another request, the advert asked for people to still shop in person, as their supermarkets were clean and still safe to visit.
And finally, they asked Kiwis to look out for fellow shoppers and staff members: "In times of uncertainty a little kindness goes a long way."
The supermarkets concluded that feeding their communities was their number one priority and if everyone worked together there would be plenty to go around.
"Thanks New Zealand - with your support, we've got this."
The supermarket chain said it cannot get some items onto shelves quickly enough if people keep buying at the current rate.
It said its supply chain is strong but it needs people to shop normally rather than stockpile.
It is putting limits of two items per customer on products such as packs of toilet rolls, hand sanitiser, personal wash, Panadol, wipes, pasta and rice.