Turkish city's stallholders voice anger over new gentrifying law that bans long tradition of shouting their wares to passersby

"White butterflies! Only three lira!" The trader at the weekly street market in the conservative Fatih district of Istanbul has few qualms about broadcasting the merits of his wares – but he is breaking the law.

A new law introduced last month aims to put an end to the long tradition of market traders singing, shouting or otherwise extolling the virtues of anything they have to sell, from teapots to potatoes. Offenders face fines and even the closure of their pitches.

Not surprisingly, stallholders at many of Istanbul's 350 markets are fuming.

"Some traders don't come any more because of the fines," Murat Simsek says. His neighbouring stallholder was shut down by the municipal police after calling out to passersby, he adds.

"In other parts of the city, markets are being closed down, and they want to finish this market as well," says Simsek, adding that the increase in supermarket chains has also had an impact.

"We always have to have one eye on the street to watch out for inspectors. But you're not a market trader if you don't shout."

"This is a ridiculous rule," says another stallholder, who did not want to be named. "Nobody here is happy about it." His colleague nods. "[Selling products on a street market] is like the lottery – you never know how much money you will take home at the end of a day. They need to let us do our job and not interfere."

He adds that the local municipality imposes a 170-lira (£60) fine for a first-time "shouting" offence, although the amount seems to vary from neighbourhood to neighbourhood. According to the market traders, the Fatih municipality – run by Turkey's ruling AKP party – is the most severe. "They don't let us breathe," says one dairy seller, a Fatih resident. "They fine you for anything – we are all fed up." Fatih's mayor, Mustafa Demir, was not available for a comment.

The measure is part of a package of laws aimed at bringing order to Turkish markets, and is designed to stop traders pestering and harassing shoppers.

In other markets and neighbourhoods, traders are somewhat luckier. Abdülkerim Bardak, a vegetable seller of 30 years, working at the Besiktas Saturday market, says the municipal police do not fine shouters immediately – warnings are issued beforehand.

In the weekly Tarlabasi market, tied to the municipality of Beyoglu, traders were feeling free to shout, saying the law had not been fully implemented by the authorities there.

Yuksel Ozdemir, who has been working at a fruit stand on the Fatih market for 25 years, says he and his co-workers would not let the law keep them from singing and shouting. "If politicians do it, nobody cares. [Turkey's prime minister Recep Tayyip] Erdogan shouts all the time." He laughs. "The men working at our stand are artists, real singers. This is part of the market culture."

One of his colleagues proves it with song: "We have apples and mandarins, such beautiful mandarins, welcome ladies and gentlemen, what a beautiful day today is!"

A lady choosing oranges from his stand agrees. "I think they should let them be, let them shout," Ayse Fevziye Sonmez says. "There is no joy in a market shrouded in silence."