SEOUL (Reuters) - As protesters march through Gwanghwamun Square in downtown Seoul, the centre stage of huge weekly demonstrations calling for South Korean President Park Geun-hye to step down, nearby restaurants hustle to prepare for a busy night.

Many bars and restaurants in the area, home to government offices and near the presidential Blue House, have been doing roaring business well into the night when the protests are held every Saturday. The boom is a relief for neighbourhood restaurants after a new anti-graft law in September limited the value of meals that could be accepted by civil servants.

Saturday’s protest calling for Park to resign over an influence-peddling scandal was the largest yet, with organisers putting the total number of participants at 1.7 million, while police say the crowd at its peak totalled 320,000.

The demonstrations taking place for six straight weekends have been festive and peaceful, with parents bringing children and protesters putting flower stickers on police-bus barricades. It’s a contrast to violent anti-government protests South Korea has seen in the past, when activists hurled rocks at police lines and were sprayed with pepper gas.

“We’ve prepared three to four times more than usual and set up seven more tables outside,” said Cho Joung-suk, owner of Gwanghwamun Yeontanjib, a restaurant specialising in grilled eel. Nearby, protesters chanted “Park Geun-hye step down now!” and “We are the owners of the country!”

Activists marched to within 100 metres (yards) of the Blue House, one holding up a red sign reading “Arrest Park Geun-hye”.

Cho, who usually shuts the restaurant on weekends and closes by midnight on weekdays, said that last week she had customers until around 4 a.m. on Sunday morning.

Kim Min-sung, a student who sat for South Korea’s high-stakes university entrance test two weeks ago, was at his third protest.

“I had been studying for the past couple of months but I felt that I had to come out and protest after the exam as the situation had become serious,” he said, taking a break at a restaurant specialising in South Korea’s famous chicken and beer, or “chimaek”, combination.

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LED CANDLES, SELFIE STICKS

The anti-Park demonstrations have featured rappers and musical actors taking the stage in Gwanghwamun Square, while protesters carrying LED candles cheer with synchronised waves. In small alleyways, vendors were selling street food, selfie-sticks and the candles.

While many business owners are profiting from the protests, the political crisis helped push consumer sentiment to a nearly 7-1/2 year-low in November. Some merchants say the demonstrations have been disruptive to their business.

Park, whose approval rating stands at just 4 percent, according to a poll released on Friday, has refused calls to step down immediately. Last week, she asked parliament to find a way and a timeline for her to leave office, but the opposition plans to bring an impeachment motion to a vote on Dec. 9.

Park is accused of colluding with her long-time friend Choi Soon-sil to enable her to meddle in government affairs.

Seo Young-pyo, a resident of Jeju Island, 450 km (280 miles) south of Seoul, came to Saturday’s protest with his 18-year-old daughter.

“It’s not that there is less passion outside of Seoul or on Jeju Island. But Gwanghwamun Square in Seoul is the centre of Korean society and there is a lot to see and learn,” he said.

As Saturday night wore on, protesters took breaks for hearty meals and talked politics over drinks. Many joined long queues to use public toilets.

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Kim Song-ryul, owner of Geosung Hof, a chimaek restaurant, said the carnival-like mood was a key driver of stepped-up business.

“There are families with young children in strollers who come to the protests and drop by our restaurant. The festive atmosphere really is a change from the past where there was violence,” he said.

The recent rise in weekend sales has been a boost for many business owners in Gwanghwamun whose core trade of serving office workers was squeezed by the anti-graft law that limits the value of a meal that can be accepted by a civil servant to 30,000 won ($25.72).

Still, Kim, owner of the chicken and beer restaurant, has mixed feelings about the unexpected bonanza.

“If our sales rose due to good business every day, I would feel better. But to be honest, I don’t feel that great about the entire situation,” he said.