The couple caught in a viral video verbally abusing and shoving an elderly man at a Toa Payoh hawker centre said they believe they have been "punished by society" over the past four months.

Mr Chow Chuin Yee, 45, and Ms Tay Puay Leng, 38, were fined in court on Friday for the use of criminal force and harassment on Mr Ng Ai Hua, 76, in April.

Ms Tay was fined $1,200 for using abusive words on the retiree, causing alarm, while Mr Chow was fined $1,500 for using criminal force.

Asked about comments from netizens that they had got off lightly with a fine, Mr Chow told The Sunday Times yesterday that they have been "living like fugitives" to prevent any further public incidents after facing backlash both online and in public.

Ms Tay, a tutor at Novel Learning Centre, said she sought psychiatric help in June, after she experienced anxiety being in public.

She is still on medication.

Mr Chow, a director at the same centre which provides tuition services, recounted an incident that took place six weeks after the video went viral.

"I took her out to have a meal at a hawker centre. But someone recognised us and started to film us, drawing a lot of attention from other people," said Mr Chow. "We were just queueing up for a meal; it's scary."

He said they have been intimidated too. "One time, this guy purposely stepped backwards while queueing up for food and stepped on my toes, hoping I would pick a fight," he said.

Mr Chow and Ms Tay were thrust into the spotlight after a video captured by a member of the public - showing the couple in a dispute with Mr Ng at the hawker centre in Lorong 8 , Toa Payoh - went viral.

Ms Tay was first seen arguing with Mr Ng, after the retiree approached the table for five, carrying his dinner and seeking to share the table.

Mr Chow, who arrived at the scene after Ms Tay called him, bumped forcefully into Mr Ng's back, causing him to stumble forward. Ms Tay said she was not thinking straight and continues to regret her rash actions. "We rushed to the hawker centre after my classes as I just needed a quick meal before going home to take care of my grandmother."

She said she had been taking care of her 89-year-old grandmother, who suffers from dementia, for the past 10 years. "At that time, she was just discharged from hospital after being warded for about a week and was not very stable. In fact, we were asleep when the video went viral because I was back at the A&E with my grandmother ."

The incident put the spotlight on "choping" culture and civil behaviour. The role of social media also figured prominently in the case, especially when another woman was wrongly identified as Ms Tay, leading to online witch-hunts against a different woman.

Acknowledging that their actions were "shameful, selfish and appalling", the couple sought to make amends to Mr Ng.

Both of them wrote a page-long letter each to Mr Ng, dated April 26 - five days after the incident on April 21 - where they apologised to him and asked for a chance to do so as well in person. They passed the notes to the investigating officer.

Mr Ng and his daughter, who had posted on Facebook recounting the incident, did not reply to queries from The Sunday Times.

His daughter Caroline wrote in a post in April: "The only reason we decided to step forward... is to bring public awareness that such (an) act should never be tolerated, to serve as a voice for those who are victimised by similar situations and to prevent such things from happening again."

The couple would like the chance to apologise to Mr Ng in person if possible. Ms Tay said: "I've offered to volunteer at the eldercare centre my grandmother used to go to."