The amount of abuse and violence Countdown shoppers inflict on its staff has increased a whopping 600 per cent during the lockdown period.

Since the lockdown began until it ended on Monday night, supermarkets were one of the few essential businesses that remained open.

Panic buying was rife during the first few weeks of the lockdown, with tensions often boiling over with disgruntled customers.

Despite the move to alert level 3 this week, Countdown stores remained busier than normal, general manager of health and safety Kiri Hannifin said.

"Unfortunately, we're still seeing a concerning level of abuse against our team and this hasn't eased off even as we transition to alert level 3," she said.

The abuse and violence were "incredibly disheartening" for the Countdown team who had worked hard to look after Kiwis during the lockdown.

Customer numbers were still being limited in stores at any one time and shoppers were required to maintain physical distancing guidelines.

Before New Zealand entered the lockdown, Prime Minister Jacinda Ardern urged Kiwis to "be kind" to one another.

It was a message reiterated by supermarkets throughout the country.

However, the message had to be repeated constantly during the lockdown with a handful of shoppers failing to register the memo.

In early April, a woman was charged with common assault after allegedly punching Warkworth Countdown's manager in the face.

The 45-year-old woman was arrested and is due to appear at North Shore District Court on May 14.

Meanwhile, the week before in late March, a Pak'nSave worker in Bay of Plenty was spat on after a confrontation with a customer.

A customer allegedly refused to stand behind the line at the butchery counter and spat on one of the workers at Pak'nSave Whakatāne.

A spokesperson for Foodstuffs, which operated New World, Pak'nSave and Four Square, thought stress could have been a trigger for violence.

Occasionally stores had to deal with people who had behaved badly and the lockdown had not changed the fact, they said.

"This behaviour, of course, is completely unacceptable and will absolutely not be tolerated in our stores at any time," the spokesperson said.

"Customers who behave in this way on our premises can expect to be trespassed and the police to be called."