"They're getting slaughtered on price by the supermarkets. It's just a mess."
Should George Weston's 150 or so union members strike, about one third of the North Island's bread wouldn't be baked.
Negotiations also begin this month with Goodman Fielder, which produces Vogel's, Freyer's and Quality Bakers bread, and Holley suspected the same outcome.
The negotiations only concern North Island bakeries.
The bakery workers, who regularly did 12-hour shifts in "stinking hot", anti-social conditions, often on the minimum wage, had had a "gutsful", Holley said.
"You can't make a loaf of bread for a dollar. It's a skilled trade where the product the workers produce is being pushed down to the lowest-price article you can buy in the supermarket and each year we're losing jobs because they're having to crank up automation on these plants because they can't make any money. So, basically, they get rid of the labour force."
George Weston managing director Mark Adam said the company empathised with the union, pointing out it had been forced to slash its workforce by about 20 per cent since $1 bread was introduced at major supermarkets in 2014.
"We as suppliers do not set the retail prices, that's at the sole discretion of retailers," he said.
The consequence of $1 bread in the New Zealand market was that more than $117 million of value had been stripped from bread sales since 2014.
"In a place like New Zealand that is a significant amount of money. That was clearly very good for the consumer but not good for the suppliers of bread [because] it places pressure on the supply prices to the retailers," he said.
"So the retailers have a lot of leverage to reduce supply prices."
Adam said that when the retail price was at $1, bread was being sold for below its fundamental economic value.
George Weston was going into the upcoming negotiations with good faith and had a "very good" relationship with its unions.
"We have had no price realisation for many years in this business - we've had price deflation," he said.
"So you just have to put a line in the sand that at a certain point you can't afford to pay people anymore because there's no profitability in the baseline business."
The company had mitigation measures in place should the union strike, he said, but would not expand on what these were.
Progressive Enterprises said in a statement that its flagship supermarket Countdown was not anticipating any bread shortages and still had its in-house range of bread and buns available for customers.
The company did not comment on other businesses and how they were run.
Goodman Fielder and Foodstuffs have been approached for comment.