Consumers in Japan have launched a campaign to tackle their addiction to plastic bags, but new measures to combat marine pollution have created an unexpected problem: the rise of shoppingfits.

A fee for plastic shopping bags was introduced in all stores in Japan in July to encourage shoppers to use their own, reusable bags instead of carrier bags.

As supermarkets and convenience store chains have seen a dramatic decline in the use of plastic bags, consumers have quickly changed their shopping habits, with a significant proportion saying that some are campaigning in shoplifts against single-use plastic.

Despite being encouraged to use regular in-store kites, some shoppers keep items in their own bags, making it harder for employees to find stolen items, ”according to media reports.

According to Gigi Press, about 80% of customers started bringing their own bags when the plastic bag charge was introduced at Akidai Sekimachi Henten, a supermarket in Tokyo. Store operators at the country’s three largest convenience stores reported similarly impressive trends, saying 75% of their customers left plastic bags in July when the charge was introduced.

However, the increase in shoplifting has forced the store to tighten security, with some light-fingered customers even using basket-fighting measures to take them home shopping instead of paying for their plastic bags.

Hiromichi Akiba, president of the supermarket chain, told Gigi, “We’re not right about spending hundreds of yen on customers carrying baskets.” “We thought we would be able to reduce costs by charging plastic bags, but instead we faced unexpected costs.”

Shop assistants say they are reluctant to confront people who accuse them of putting items in reusable bags with the intention of leaving them unpaid. “It’s hard to judge if they’re stealing,” said a Tokyo supermarket employee.

In response, a nonprofit group has created posters advising customers “for shopping etiquette” such as folding their reusable bags before going through a checkout.

An expert in shoplifting advised employees to stay away from ways to chat with shoppers “to keep an eye on them”.

Despite the rise in petty crime, promoters say Japan, the world’s second-largest producer of plastic waste per capita after the United States, has long been charged with plastic bags, with consumers receiving an estimated 30 billion plastic bags a year.