A dozen eggs for $6.80 or a dozen eggs for $3.25? It costs a lot to support eggs from cage-free hens.

The beanie-wearing man pulls a carton of caged eggs from the Pak 'n Save egg shelves, hesitates, then slides it back.

​"I'm having a bit of a guilty conscience," he says. "I feel I should do the right thing, you know, those battery hens, but ..."

It's the price, isn't it?

"Well, yeah, it's hard but you need everyone on board to make a change," he says, staring at the shelves.

READ MORE:

* Shocking video of colony farm hens

* Battery hens go from death row to the good life

* Is this New Zealand's youngest chicken farmer?

But when he thinks I'm not looking, he plucks out the caged eggs and walks off.

Caged-egg producers say Kiwis should have this choice. Animal rights campaigners say the issue is bigger than money.

Look at any supermarket egg section and you'll see this battle of ethical versus economical in wildly different prices and packaging.

EWAN SARGENT/STUFF Cage-free options are filling the egg section of supermarkets.

At this Pak 'n Save, a dozen Farmer Brown free-range mixed-grade eggs work out at 58 cents each. Colony-cage eggs are 30 cents each, while standard caged eggs cost just 25 cents each.

Cage-free eggs take up at least half the space at most supermarkets and in some it's much more more even, though two-thirds of supermarket egg sales are caged eggs.

That's because caged eggs are doomed.

The egg world is in turmoil at the moment as caged-egg producers struggle with the idea that even though they can give us cheaper eggs, we either don't want them, or the biggest sellers, the supermarkets, don't want to sell them.

EWAN SARGENT/STUFF Egg producers thought colony eggs were the answer and the packet doesn't mention the "cage" word, but colony hens are still caged.

All major supermarket chains – Foodstuffs (Pak 'n Save, New World, Four Square) and Progressive (Countdown, Fresh Choice, Super Value) – have set dates from which they won't sell eggs from caged hens.

For Progressive it is North Island 2024 and South Island 2025; for Foodstuffs it is 2027.

You can imagine a huge collective "what the" from caged-egg farmers when the supermarkets made the call. They sell about 55 per cent of the about 1.1 billion eggs laid a year, so what they do matters a lot.

The farmers would have thought they were on the right track when, in 2012, the rules were changed to make egg farming more hen friendly.

PETER MEECHAM/STUFF Egg Producers Federation chief executive Michael Brooks says the spurned colony cages meet welfare needs for hens.

The Government said old-style battery-hen cages had to go and accepted colony cages as a replacement. This gave hens more room – up a couple of hundred centimetres per hen to 750 square centimetres – plus some perching, nesting and scratching areas.

It was a completely new system and expensive to move to, and egg farmers have their own transition period, running with old cages swapped for new colony cages by 2022.

Egg Producers Federation executive director Michael Brooks says moving to colony cages is partly about good animal welfare and partly about being able to keep supplying affordable eggs.

He says the colony cages solve welfare worries and quotes the National Animal Welfare Advisory Committee, which says colony cages "provide equivalent or superior overall welfare" compared with barn and free range.

"The decision by supermarkets five years later in 2017 to change their purchasing behaviour was done with limited notice and knowing many longstanding suppliers had spent millions of dollars converting to colonies," Brooks says.

Changing to barn and free-range businesses is complex and expensive. Free-range farms mean new sites, they need more land, and they have more labour costs compared with cage farms.

"As a result, we have seen farmers who had advanced quite some distance down the colony route having to completely rethink their options," Brooks says.

Egg farmers believe the continued popularity of cheap eggs shows public opinion isn't as set against cages as is often claimed.

"We would argue that the decision of the supermarkets to take away consumer choice is not based on credible welfare science or a dramatic drop in public purchasing of cage or colony eggs," Brooks says.

This image of hens happily wandering fields is how egg buyers want to think of them, but when it comes to paying most want a cheap egg.

Supermarkets say they are going cage-free because it's what shoppers want.

Antoinette Laird, of Foodstuffs, says their in-house Pams brand has been cage-free for 10 years.

She says cage-free egg sales in all supermarkets have climbed from 33.3 per cent to 36.7 per cent over the last three years. A decade ago it was 20 per cent cage-free.

While the increase is slow, "it is most definitely on the rise".

Countdown's Nikhil Sawant says animal welfare increasingly matters to customers, which is why free-range eggs, chickens and free-farmed pork are on the rise.

"We're seeing our shoppers wanting to better understand where their food was farmed and how animals are cared for," he says.

Countdown would like to go cage-free earlier but it has to wait for free-range egg farmers to crank up production.

KIRK HARGREAVES SAFE's Hans Kriek says egg farmers were warned not to continue using cages for their hens.

Safe's (Save Animals From Exploitation) Hans Kriek claims a change of tactics helped win the supermarket move.

"They [big caged-egg producers] lobbied very, very hard when the Government was finally looking at getting rid of standard battery cages to have that in favour of colony cages because the main reason was it was a lot easier for them to convert their existing shed to a colony shed."

Safe decided to go to the supermarkets instead of relying on lobbying the Government. It asked the supermarkets to ask customers what they thought.

"The supermarkets did that. They found that people found battery cages unacceptable and it was time to move. And the same for colony cages, which is just another battery cage."

Kriek says egg farmers made a big mistake pushing for colony cages.

"We told them that right from day one. Don't go to a colony-cage system because it's just another cage and consumers are not going to like it. And a future government is going to ban it anyway. They were saying 'no, no, no, it's an acceptable system', but unfortunately quite a few people invested money in it and now their market is disappearing."

It seems the urge to back free range is strongest when people are confronted by what eggs they are buying.

SARAH CODDINGTON/STUFF An anti-battery hen protest in 2011. Protests failed to stop the new rules allowing cages to continue but supermarkets have brought in their own anti-cage rules.

In 2016, McDonald's also bypassed the colony-cage option and went for free-range eggs throughout the country. New free-range egg farms have been built to fill all those Egg McMuffins.

A McDonald's spokesman says the company is proud to have been one of the first major businesses to go free range only and at the time it was taking 9 per cent of all free-range eggs in the country. He says it was because customers supported it and so did franchisee holders and egg suppliers.

Wholesaler and distributor Capital Eggs is a big supplier to the Wellington hospitality industry and general manager Laurie Watkins says the move to free range has been a dramatic shift.

His business is now about 50:50 free-range eggs to caged eggs, with free range perhaps slightly ahead.

But there's also a big split depending on where the eggs are going. Restaurants and cafes want free range so they can tell customers that's what they use, "but your ordinary bakeries, they just want to have caged eggs. They just want eggs they can bake with. So there's still a significant demand for that."

This sounds a bit like what is out of sight is out of mind, and even Kriek admits that.

"Look at any survey and you will fnd 8 out of 10 people say [caged eggs] should be banned. Yet many of those people when they go shopping just don't think, and buy the cheapest egg."

​Kriek says the higher cost is just the cost of not having a cruel system and eventually it won't matter.

"There are supermarkets around the country that haven't been selling caged eggs for years because the managers themselves have said they don't want to contribute to cruelty and interestingly enough it hasn't impacted on sales.

"People buy the cheapest egg and that happens to be a barn egg. For some people, if the dirt-cheap eggs aren't available they simply buy the next dirt-cheap egg, whatever that might be.'

Safe still wants an official ban on colony cages even though he's heard from industry people that nobody dares invest in colony cages given half the market has disappeared. "You would be pretty dumb to invest in colony cages now."

In the egg aisle of a Countdown supermarket, a shopper says she is back here after living in South Australia where caged eggs were banned by her supermarket years ago.

"New Zealand is lagging way behind," she says.

So she buys free-range eggs, right? Um, she says, looking away. She buys the cheap ones in New Zealand.

UNSCRAMBLING OUR EGGS

Battery: All conventional battery cages have to be gone by 2022. Farmers say this method allows efficient farming with fewer animal health problems. But the cages limit the natural behaviour of birds. For cages built after 2005, hens must have a minimum of 550 centimetres square each, with no perches, scratching or nesting areas.

Colony-laid: Colony cages have up to 80 hens which get a minimum of 750 centimetres square. They can scratch, nest and perch. But animal rights group Safe says the area is still too small.

Barn-laid: Hens live in sheds with a litter floor, perches and nest boxes. They don't go outdoors but there can be only seven hens per square metre.

Free-range: Farmers can have up to 2500 hens per hectare outside, and nine hens per square metre inside. They must have access to the outdoors and "best practice" dictates they have some shelter.