Hell said 70 per cent said they would buy the pizza again.
Ben Cumming, general manager of Hell Pizza, said the company conducted the experiment to introduce Beyond Meat to customers in an unexpected way.
"We care about the planet and want to start a conversation and raise awareness about sustainable food choices.
"A lot of people are instantly put off by the idea of fake meats, so we made the call to not reveal its meat-free origins to eating it because we were so confident they'd enjoy these patties," Cumming said.
Hell, which has a network of 70 stores located throughout the country, had so far this year sold 35,000 vegan pizzas, and expected the trend to continue, he said.
"With more pressure on the planet's resources, we need to think about alternative food options. If covertly adding meat-free options onto a pizza encourages more people to be open-minded, we're happy to do that."
Mark Blackham, director of public relations firm BlacklandPR, said he was appalled that Hell had misled consumers who had bought a pizza not knowing it was meat-free.
"The phrase 'medium-rare burger patty' is understood by a reasonable person to mean there is meat in there somewhere. Hell knew that, and brazenly admits to not telling customers. This behaviour cannot be sanctioned," Blackham said.
"It is not okay to lie just because you think you're on the side of 'good'."
Blackham said he was gobsmacked by support for Hell from consumer institute Consumer NZ, who had previously critisied dairy giant Fonterra for "using claims that are unclear or may potentially mislead consumers" and companies that used the term 'cage-free' for "misleading shoppers about what they're buying.
"An organisation protecting consumer rights is supporting a company that dupes consumers ... That's unacceptable. The rule is that customers get the information they need to make a good choice."
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Posted by Hell Pizza on Wednesday, 26 June 2019
Hell Pizza is one of a handful of mainstream fast food chains to temporarily dabble in the meat-free meat market.
Burger Fuel in May teamed up with Los Angeles-based Beyond Meat to launch its first plant-based burger 'Beyond Beleaf'. The burger was available for a limited time in its 56 stores throughout the country. The launch coincided with 'Meatless May'.
Even Burger King has recognised the appeal of vegan 'meats'. In May, the fast-food chain announced that it would start testing the Impossible Whopper, made with a plant-based burger from Impossible Foods in its stores overseas.
Furniture giant Ikea has also said it was working on developing a plant-based Swedish meatball, which it plans to test with customers next year.
Investors have a big appetite for fake meat.
The shares of Beyond Meat, the purveyor of plant-based burgers and sausages, more than doubled in its Nasdaq debut earlier this year.
The company is the first pure-play maker of vegan 'meat' to go public. Beyond Meat raised about US$240 million ($363m) selling 9.6 million shares at $25 each. Those shares rose 163 per cent to close at $65.75.
