Countdown competitor The Mad Butcher has made fresh allegations of bullying against the Australian-owned supermarket chain.
It comes after Labour MP Shane Jones alleged Countdown owner Progressive Enterprises had blackmailed suppliers into making retrospective payments to keep products on shelves.
The Commerce Commission is currently investigating allegations of anti-competitive conduct.
Speaking on TV3's The Nation today, Mad Butcher chief executive Michael Morton made further allegations of suppliers being pressured by Countdown.
Asked whether suppliers were being pressured to not deal with his company, Mr Morton said the matter was before the Commerce Commission.
"But I think the New Zealand consumers should make that decision for themselves.''
When pressed, Mr Morton said he believed the supply chain was being squeezed.
"Any company that controls 50 per cent of the market in New Zealand has a lot of weight. And if they choose to throw that weight around in an un-New Zealand-type fashion, then I believe that suppliers would definitely be scared to upset them.''
Mr Morton was not a supplier to Countdown himself.
"But I've definitely had comments from suppliers where that has been brought up to me, that they had pressure put on them.''
There was "a culture of bullying within the whole organisation'', Mr Morton said.
The Mad Butcher got "smashed with lawyers' letters'' and complaints to the Advertising Standards Authority when the company engaged in comparative advertising claiming its products were cheaper.
"They come down like a sledgehammer with lawyers letters,'' he said.
"They're being bullies because they believe that they're big and they're powerful, they can send us all these letters, they have lawyers on staff, they have some of the biggest law firms in New Zealand working for them, and they think they can tie you up with that litigation.
"I'm trying to stand up for the little guys here of New Zealand, and say, 'Listen New Zealanders, you should support the little guys here in New Zealand.'''
Local Government NZ president and Hastings Mayor Lawrence Yule said supermarkets were also fighting against councils' attempts to limit the hours alcohol could be sold.
He told TV3's The Nation that councils wanted to adopt 9am to 9pm hours, but the default position from supermarkets was for 7am to 11pm.
Countdown in particular had appealed on the basis it wanted supermarkets open until 11pm, and supermarkets had even applied for extended hours in areas like Hauraki where supermarkets were not open after 9pm.
"I think they need to be more cognisant of what local people want,'' Mr Yule said.
"These are local policies - they're meant to be designed by local communities, that's effectively what the government said - and they've got to recognise that in many cases, a lot of communities around New Zealand are concerned about alcohol-related issues and the hours of operation.''
Eighteen local councils were putting through new alcohol policies under the new law. Those policies were subject to more than 60 appeals.
Mr Yule said councils were considering pooling funds to fight the legal battles. The cost of Hauraki's appeal alone was about $20,000.
Countdown declined to appear on The Nation but in a statement, it denied any anti-competitive behaviour and said it was cooperating with the Commerce Commission.
The company said The Mad Butcher was a direct competitor but was welcome to raise concerns about suppliers directly.
On the alcohol issue, the company said it had worked with local councils for months. It had appealed only 13 council plans, which was its legal right. The appeals would help to clarify the new law.