Some grocery shoppers do more than walk down the aisles - they get a push-down instead.
Miss Yan Fen, 44, was appalled to see a woman in her late teens to early 20s sitting in a trolley and taking selfies at the NTUC FairPrice Xtra branch at Nex mall, in Serangoon, around midnight on April 20.
"On weekends I can easily see eight trolleys with children in them," she said.
"But this adult in the trolley was too much. She was very proud of it."
Miss Yan sent the pictures to citizen journalism website Stomp, saying: "They are using it like a human toy car!"
On Stomp, other users had previously sent in pictures of people misusing trolleys at other NTUC branches, like Changi Airport and Ikea.
On joyriding in trolleys, an Ikea spokesman said: "Those who misuse our trolleys will be advised not to do so for safety reasons. Safety is one of the key priorities at Ikea."
Miss Yan, who buys groceries at the NTUC in Nex mall, said she has been seeing more parents letting their children ride in trolleys, outside the child seats, over the last year or so.
Sitting in the main compartment of a trolley is not allowed. Signs near FairPrice trolley bays advise that children should sit only in the child seats.
Miss Yan understands that some parents put their children in the trolleys as they do not want them running around.
But she feels it is unhygienic because children wear shoes in the trolleys.
She said some supermarket staff would ask customers to take their children out of the trolley, but most just let them be.
A FairPrice spokesman said that all staff are briefed on proper trolley usage, and trolleys are cleaned regularly.
"Sitting in a trolley can be dangerous and could hurt the person in the trolley should it collide with other shoppers or topple over," he said. "Such use is also unhygienic, since trolleys are used to carry food."
The New Paper went to FairPrice Xtra at Nex mall on Wednesday evening and saw one child, who appeared to be around five, sitting in a trolley in her shoes. Her mother and younger sister were walking and pushing the trolley.
The girl's mother, who declined to give her name, said: "She runs around and hits other people and things."
She felt it was safer for her daughter to sit inside. She also checks to see that her daughter does not stand in the trolley.
One trolley user, a civil servant who gave his name only as Kamalludin, 44, said climbing in and out of trolleys was dangerous, and children's legs may get stuck in them.
"It's up to parents to teach children to do the right thing," he said.
Housewife Mariamah Veliapan, 62, thought younger children, "two to four years old", could sit in trolleys. She also said the parents, not the children, should be blamed if children sit inside with their dirty shoes.
But she does not allow her grandchildren sit in them.
"It's not clean for the children or the food," she said, referring to trolleys being also used for raw food, such as meat.
Miss Yan said some shoppers put their own foldable trolleys with wheels inside the bigger supermarket trolleys.
One such user was Miss Susie, 65. She thought children sitting in trolleys was unhygienic, but putting her own trolley in was acceptable.
But she started wheeling it on leaving the supermarket.
This article was published on April 29 in The New Paper. Get The New Paper for more stories.