Hotels are increasingly moving away from the idea that the customer is always right and standing by their staff when facing abusive customers.
They join other sectors, such as health care and retail, which have also taken measures to protect their staff from potential abuse.
"These days, the customer is not king any more," said Mr Patrick Fiat, general manager of Royal Plaza on Scotts. "The service industry does not accept aggressive and unreasonable behaviour from guests."
He cited an example of a guest whose children were screaming and rolling around on the floor at the hotel's buffet restaurant. When staff approached the man and requested that he attend to his children, he hurled vulgarities at them and left without paying for the meal.
"We stand firmly against such behaviour from guests," said Mr Fiat. "If a guest does not show respect for our associates, we will make it known that our associates should not and will not be abused."
The chief executive of Far East Hospitality, Mr Arthur Kiong, said there is a "gradual move" away from giving in to abusive customers' demands to taking a "careful and considered" approach in making sure the root of their complaints is addressed. Solutions have to help not just the customer, but the staff as well, he added.
The veteran industry players attribute the shift in mindset to the rise of social media and changing attitudes towards what is "acceptable" customer behaviour.
The younger generation is better educated, more vocal and wants a work environment where employees are respected and valued as individuals, said Mr Fiat. "They want to participate in decision-making and understand why they are doing the things the management tells them to do."
One way organisations can manage this new generation of service staff is to turn them into experts in the service or product they offer, thus lifting their status on a par with their customers, said hotelier Jennie Chua.
The judging panel for next year's Singapore Service Excellence Medallion will be looking out for organisations with such "empowering" service cultures, added Ms Chua, who is also the deputy chair of the 15-member panel.
Nominations for the third edition of the biennial award close today.
"Empowerment is by giving proper training," said Ms Chua, former general manager of Raffles Hotel. "If you don't know what you're selling, you can smile, have the best attitude, but the customer will still not regard you as a partner in the relationship."
In recent years, other sectors have made their stand against abusive customers clearer.
In health care, Changi General Hospital and the National University Hospital have signs around their facilities reminding patients to treat staff with respect.
Retailers such as telco StarHub and bathroom product retailer Sim Siang Choon have similar signs at their outlets.
"It's a pre-emptive measure, it's not that we have rude customers," said Sim Siang Choon's assistant director, Mr Gary Sim, 32. The signs were put up at its cashier counters about two years ago.
SBS Transit launched a "Stop Bus Captain Assaults" campaign in 2007 after a spike in attacks on its drivers. Signs that say "No assault on bus captain" were put up in buses, while posters were put up at all its bus terminals and interchanges. They read: "Our bus captains have the right to work in a safe environment like everyone else."