AT YOUR SERVICE: Madison Shaw, 4, and her collectables in one of New World’s new mini-shopping stall.

Mock miniature groceries are delighting youngsters, emptying parents' wallets and sparking warnings about the power of marketing to children.

New World supermarkets have run out of Little Shop accessories - scales, tills, trolleys and baskets - and the miniature groceries collectables are in high demand.

A set of the 44 miniatures fetched $540 on Trade Me last month, and a Facebook page dedicated to swapping the groceries has attracted 1470 members.

Some kids have even taken to stealing them. A Tauranga teacher, who did not want to be named, discovered two of her male pupils stole the groceries from another boy's desk at lunchtime.

She said at times she has to confiscate the toys from her class of 7 and 8-year-olds.

Surprisingly, they are most popular among boys, she said. "They are more of a status thing, a ‘Look, I'm cool because I've got them'. They don't really play with them, they just swap them to create a set."

West Auckland 4-year-old Madison Shaw twisted her mother's arm into shopping at New World so she could kit out her toy shop at home.

The Marmite jar, Vogel's bread and Pump bottle are favourites among her friends because of their likeness to the real things, mum Verity said.

"They will swap so they have the whole set, but when no one's looking Madison will swap hers back again. She absolutely loves it.

"I have a 15-week-old boy and he has to play shops as well. We all have to play shops every day."

The Shaw family would split their shopping between New World and Countdown, which has a promotion for cutlery at the moment - but "the little food outdoes the cutlery" at the moment, says mum.

The collectables are available with every $40 spent, with additional merchandise including a Little Shop stall to set up shop.

The concept originated from supermarket chain Albert Heijn in the Netherlands, working with Dutch toy design studio Unga, which makes the minis in China.

Everything is made from a mixture of cardboard, foil wraps and plastics, and has passed toy safety standards.

Steve Bayliss, group general manager marketing, Foodstuffs NZ, which owns New World, said the company met with Unga "to see if we could adapt the idea for New Zealand and in particular for New World as part of our 50th birthday celebrations".

The Dutch store created the miniatures for its 125th birthday celebrations last year. They offered 51 items, each available for every € 15 ($NZ25) spent. Products included Dutch products such as Vissticks fish fingers and their own versions of breakfast cereals.

The minis proved a hit there too, being traded on the Dutch website equivalent of Trade Me.

Bayliss said New World had been approached by "several educational organisations" wanting a full set of collectables to use as part of their curriculum. "In particular, we have been approached by teachers of children with special needs, commenting on the benefits of using the mini-collectables to help their children in their role play."

Health watchdogs say the campaign is "clever" by featuring trusted brands such as Milo, Marmite, Weet-Bix and Wattie's.

There are also treat items - Whittaker's chocolate, Tim Tam biscuits, Tip-Top icecream and Bluebird chips. New World would not reveal how the products were chosen or what was involved in companies taking part, just that "we invited a wide range of suppliers that reflected every category within a New World store".

Researchers at Consumer NZ say it's an example of the increasingly "pervasive" nature of food advertising. "It includes toy chocolate, chocolate biscuits, chippies and tomato sauce," research and testing manager Hamish Wilson said.

"Yes, there's a toy apple and banana as well - but we think it's rather unbalanced."

Wilson said parents were "under seige" by food companies and many don't realise it, he said.

The latest Consumer magazine points to several ploys marketers use to manipulate kids - such as fun packaging, cartoons, associating with movies, offering collectable toys and putting a "healthy spin" on advertising.

Health experts are only too aware of the impact of establishing brand loyalty at a young age.

"It makes food fun for kids," Agencies for Nutrition Action spokeswoman Julia Lyon said.

"Kids are consumers in their own right with pocket money, but for marketers they are future consumers. Positive brand recognition carries into adulthood."

Requests for the collectables have also come from teenagers, adults and even grandparents, Bayliss said.

A Hamilton woman who tried selling the complete set on Trade Me days after they appeared in supermarkets last month attracted more than 26,000 views with her listing. The full collection of miniatures, with shopping basket and tin, fetched $540.

Trade Me estimates there are at least 1000 individual Little Shop listings, even though onselling is technically forbidden.

The promotion ends this month.