He was shoved and jabbed repeatedly in the chest by a burly customer a few years ago.
All Mr Bjorn Shen, 32, did was to tell his customer about the no-split-billing policy in his Middle-Eastern restaurant Artichoke.
"He started getting abusive, hurling vulgarities, grabbing collars and eventually I almost got into a fight with him," the chef-owner told The New Paper.
It was finally settled with him throwing the customer's credit cards back at him, telling him that his $450 meal was free and to never return.
"He went back to his table, exclaimed 'Dinner was on me!' and walked out with his friends," Mr Shen said.
While such extreme cases are a rarity, those in the service industry like Mr Shen are no strangers to unreasonable or rude customers.
He said his front-line staff have at least five run-ins with customers who are verbally abusive or plain condescending every week.
Perhaps the most pushy are people with babies and young children, he said.
"I call them 'Baby Bargers' - unreasonable people with no reservations, and who barge in using their kids as blackmail," he said.
Bartender Dave Koh, 34, has had a customer yell at him once a few years ago - all because he could not make her a creme brulee, which requires using a flame to caramelise the dessert.
When the bartender at Bar Stories told her he could not do it as everyone was busy, she began to sulk, then yelled at him, before storming out of the place.
"It was discouraging. I always see serving customers in a bar like having guests at your house.
"You want your customers to feel that same level of warmth," said Mr Koh, who added that he was relatively new at that time.
He recounted another incident over the weekend, when a female customer who "turned nasty" after being told Bar Stories, which specialises in crafting cocktails, does not serve wine.
"She was put off. She was a little rude in her tone and maybe a little condescending."
But thankfully, such customers are a rarity, Mr Koh said.
"There is a flash of annoyance and irritation sometimes, but we don't show it.
"I always tell my guys not to take it personally, and at the same time, try to switch from being confrontational to solving the problem," he said.
For Artichoke's Mr Shen, however, it is difficult to ignore the unreasonable customers, no matter how much of a minority they are.
"It really eats into our souls and no matter how hard we try to be unaffected by it, each hit we take still hurts...
"It's hard to feel good about ourselves when even a minority of people keep treating us like dirt."
This article was first published on May 7, 2015.
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