Upon hearing that he could not pay for his purchases with an unsigned credit card, a customer at OG department store started swearing and called the staff "stupid".
When they tried to placate him, he retorted: "I am the customer, I have the right to call you stupid."
He later relented and paid cash, says an OG spokesman. "Perhaps the customer felt he was superior," he adds.
Staff usually try to mollify customers who throw hissy fits - such as threatening to get service staff sacked - while attempting to exchange undergarments, altered clothing and even an unused bag that had been stowed away for two years, says the spokesman.
Labour chief Lim Swee Say called for a "nation of better customers" last week, saying overly demanding customers would aggravate the labour crunch.
A check with 18 F&B and retail outlets here showed that Singaporeans still have some way to go to meet this goal. While they often gripe about bad service, there are just as many examples of ungracious customer behaviour.
Frontline staff have come across customers who hurl profanities, insist on eating food bought from elsewhere in a restaurant and ask shop staff to run errands. Other common gripes include no-shows at restaurants after making reservations and clicking one's fingers to summon the waiter, says Ms Janet Lim, 34, senior group public relations manager of Spa Esprit Group, who has seen diners do this at its Skinny Pizza eateries.
Handling such behaviour is all in a day's work for those in the service industry, says Mr Tan Ken Loon, 39, who owns seafood restaurant The Naked Finn. He recounts an incident where a man pushed his restaurant's general manager and shouted profanities when he was told there were no baby chairs available.
Another man came to dine with his children and helper toting takeaway fast food. When told that food from elsewhere could not be consumed on the premises, he took out portable chairs and a table from his car and plonked them by the door of the restaurant for his children and helper.
At Cups N Canvas cafe, a customer once ordered coffee and insisted on eating her packet of economy rice there as well, cafe manager Yeo Kim Hock, 33, recalls. He acceded to her request as he did not want to create a "big fuss".
Wines and spirits retailer 1855 The Bottle Shop allows customers to pack their own food, which they can pair with store-bought tipple at selected outlets. But some would push their luck by asking for napkins, nuts and drinking water. There are also those who ask the staff to run errands, such as getting soft drinks from a supermarket to go with store-bought whisky, says manager Tan Lee Kim, 44.
Mr Ivan Teo, 38, director of Arteastiq, recalls how a customer once got on his phone in front of the wait staff and urged his friends to boycott the tea lounge after he was served soup without bread, which is sold separately.
And when staff at buffet restaurant Carousel at Royal Plaza On Scotts approached a diner whose children were screaming and rolling on the floor of the dining area, they were greeted with obscenities, says general manager Patrick Fiat. The family also left without paying for their meal.
They are a classic example of customers who try to exploit a situation. Marketing professor Jochen Wirtz of the National University of Singapore Business School says: "The minute something goes wrong, some customers try to cause a big commotion to get a bill waived, an upgrade or some other out-of- proportion compensation."
Those who haggle are another bugbear of the service industry. At French restaurant Bistro Du Vin, "crafty customers" try to have the $30 corkage fee waived even when they bring pricey bottles of wine that cost about $300 or more, says director Philippe Pau, 50.
To do so, they would tell staff that the manager usually does not charge them corkage. "They try to pull a fast one, but they don't see the additional work that we do, such as table service and washing the glasses and decanters," says Mr Pau.
The problem also lies in the fact that Singaporeans generally deem service staff to be of a lower social position. As Mr Pau puts it, being a waiter is "pretty much a last option" here. The Frenchman, who has lived in Singapore for 17 years, says that while service is a "craft" in Europe, it is viewed as a lowly job here.
But these horror customer stories are the exception rather than the norm, say retailers and restaurateurs.
Mr Paul Tan, a business administration lecturer at Singapore Polytechnic, says: "We may have developed a perception that Singaporeans generally behave badly towards service staff as we tend to remember the poor experiences rather than the good ones."
There is also a "sense of indifference and disengagement" among Singaporeans, adds Ms Angeline Chin, a hospitality and tourism management lecturer at Temasek Polytechnic's School of Business. "Service staff are sometimes treated like a cog in a process rather than someone whom they can work with to create a meal experience."
There are, of course, examples of good customers too. Nanyang Optical, Japanese lifestyle retailer Atomi, IT retailer Challenger, SingTel, Marina Mandarin hotel and Prive and RE&S restaurants are among service operators who cite encounters with pleasant customers. These include diners who thank wait staff by name, write thank-you notes and buy flowers, food or drinks for service staff.
Dealing with prickly customers and tricky situations requires care and sensitivity, say business owners. The Naked Finn's Mr Tan tells staff they must always explain the reason behind a decision.
"You can't say, 'Oh, my boss wanted it this way', and leave it at that. Diners are bound to get angry."
As Singaporeans become more well-travelled, they have come to expect service standards similar to those in countries such as Japan and the United States, says restaurateur and cookbook author Violet Oon, 64.
Service is a reciprocal relationship, she notes.
"I tell my servers to think of customers as people going to their house for Hari Raya or Chinese New Year. When they treat customers as guests, people are usually polite in return."