The clamping company that triggered a flood of complaints through its actions says unfair publicity has created a "mob mentality" and put its workers at risk.
More than 60 people have contacted the Herald to complain about the practices of NZ Wheel Clamping's staff, with many alleging intimidation and abuse.
Police have become involved in heated disputes, and Consumer Affairs Minister Simon Bridges has met the company and others in the industry to draw up a voluntary code of conduct.
But Sean Hika, group manager at NZ Wheel Clamping, has contacted the Herald to complain that the publicity had put his staff in danger.
"The level of abuse has grown exponentially. The threats of violence ... my guys were spat at [on Saturday]," Mr Hika said. "There seems to be a complete disrespect of the small business owner and their property rights, which is what we're looking after."
People who had their cars clamped were noticeably more abusive and passersby would join them in support, he said.
"There's almost a mob mentality building ... those types of stories, they're hurting our guys out there ... [the] threats just makes a tough job even harder."
The response came after a front-page article this month on Glen Vickery, who was awarded $550 after a disputes tribunal ruled NZ Wheel Clamping's warning signs were unclear.
But Mr Hika said he was confident the company's signs were "crystal clear". "We've won 99 per cent of the disputes that have ever been taken against us. It's only recently, since public opinion has changed, that in my opinion has it started to fall back the other way.
"And it can do that ... but the type of media it's getting, people are reading the stories as if they were precedent set in court ... a disputes tribunal cannot set the precedent."
While most people who complained to the Herald were charged $180 by NZ Wheel Clamping, others said they were charged up to $250 in the same Manurewa carpark.
Mr Hika said amounts charged did vary according to where the vehicle had been left. He said while fines could seem high they reflected the company's costs - which had risen after the negative publicity.
"It's the cost of doing business when the public are ripping our clamps off, they're smashing the clamps ... they're $160 each."
Asked if clamping was a lucrative business, Mr Hika said: "You wouldn't go into a business that wasn't, would you? We've got a lot of overheads, we're only a small business."
NZ Wheel Clamping offers its services to businesses for free and recoups costs through clamping payments, and Mr Hika rejected suggestions that shop owners got paid a kick-back on clamps.
While an industry-wide code of conduct is being drafted, Mr Hika said NZ Wheel Clamping already had an effective appeals process. "It's conducted independent of the enforcement office. It's a third party, it's another one of our team ... out of our main office, they're in their own office."
Several complainants have alleged the company's call centre operators told them to "f*** off" if they didn't have the money to pay immediately.
But Mr Hika said people were told about the appeals process if they say they want to appeal against a fine.