“It’s literally saying, ‘I want to see women’s nipples.’ I’m not individually offended, but I think it should be called for what it is: sexual exploitation. It perpetuates misogynism,” O’Keefe, 37, says.

“As a bar you have a responsibility to take care of people. I hear lots of stories of people having their drinks spiked [in bars throughout Hong Kong]. This misogynistic agenda is saying, ‘Come down here so we can all ogle at you.’ It’s a c***** marketing strategy and shows desperation,” O’Keefe says.

Carnegies bowed to the pressure of complaints on social media and pulled the event. The bar declined to comment for this story.

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Hong Kong DJ Janette Slack, who is a regular on the Hong Kong club circuit and performs at venues around the world, says despite her liberal outlook she was still shocked. She sees Hong Kong as a sophisticated city, so thought it “insane” that a club could even consider such a promotion.

“I think people should do what they want as long as they are not hurting anyone, but there is a line and this crossed that. It takes a lot for me to feel prudish – I thought that was pretty out there.

“This first thing I thought was: ‘Who is going to check?’ It’s gross,” she says, adding bars can attract people without resorting to degrading women.

O’Keefe points to Bobby’s Rabble on Wyndham Street as a bar that runs regular promotions without exploiting half its customers. It runs comedy nights, pub quizzes, live music, inspirational talks and drink-promotion nights.

“This is how you do promotions and still make it work without ‘being that guy’. It’s ‘Hey, everyone come to the bar and have a good time,’” O’Keefe says.

David McEwan, owner of Bobby’s Rabble, sees ladies’ nights as an outdated legacy of the 1980s and ’90s.

“I think they are old-fashioned, naff and don’t speak to equality and empowerment. It’s more to do with baiting to fill the bar with girls that will get guys in. It’s not my way of doing things,” McEwan says.

His bar’s answer to ladies’ night is a promotion called “Pink”, held on Thursdays, where he works in collaboration with suppliers to promote drinks like rose wine and strawberry gin.

“It’s a promotion based around the colour which is historically more female, but also appeals to the LGBT community and is not exclusive for women,” McEwan says. Ten per cent of profits from the night are donated to a women’s education charity in Cambodia, he adds.

McEwan suggests the city’s long-standing bars need to move with the times and update their image or concept if they are to stay relevant.

Ladies’ nights originated in the West, but are now prohibited by the Equality and Human Rights Commission in the United Kingdom as unlawful discrimination and also banned in some parts of the US.

Hong Kong’s first ladies’ night was hosted in 1994 by Westworld, a now-defunct club in Wan Chai, as a way to attract customers on an otherwise quiet weekday evening. They quickly became a fixture on the nightlife circuit.

“Traditionally in Hong Kong, Wednesdays have been ladies’ night in Wan Chai, coming after the horse races,” McEwan says. “And historically, Thursdays were ladies’ night in [the city’s] Central [business district].”

But that once sure-fire formula of free drinks as bait to attract women, which in turn pulls in men, seems to be losing its magic.

A recent ladies’ night promotion at Franks in Central, which offered free Aperol Spritz drinks all night for women every Wednesday, wasn’t successful, says Joshua Chu, F&B director for Red Sauce Hospitality, which runs Central venues including Fini’s, Franks and Posto Pubblico.

“We ran it for four to six months and stopped it recently. It wasn’t working. There were nights we had only ladies and other nights it was all guys and no girls. It was inconsistent so we decided to scrap it,” Chu says.

Instead, Chu and his team have opted for a happy hour promotion – cut-price drinks from 5pm-7pm with free nibbles – which are available to everyone, no matter their gender.

The Bungalow on Central’s Wyndham Street – a French restaurant that morphs into a pumping, cocktail-swigging club at night – has a ladies’ night on Thursdays. Women get one free drink of their choice, but the manager says it’s not a big drawcard.

“We offer one free drink, but it’s not really attractive. Women don’t come just for a free drink – they can buy their own drink. Times are changing,” venue spokesman Thapa says.

Slack says Hong Kong is an expensive place to live and she doesn’t want to see ladies’ nights disappear if it means fewer opportunities for women to get out and mingle. Instead, she would like to see promotions that offer cost-effective options for both sexes.

“If we are moving with the times, the bars that seem to be doing well are the ones that offer a free-drinks hour for both sexes,” Slack says. “If both sexes are welcome and they will be doing the same thing, then they’ll probably stick around more.”