Open 24 hours a day, self-service launderettes offer convenience for people needing to wash and dry clothes - but it seems they are not the only "customers".
With no staff on hand, such launderettes are also a magnet for homeless people looking for a place to sleep and a "playground" for kids who climb inside the washing machines and dryers.
Launderette owners tell The Sunday Times that their cameras have even spotted couples turning off the lights at night and using the space as a dating spot, with a few caressing and hugging each other.
The owners have also had to deal with their customers' dirty belongings, such as muddy army helmets, stained dog beds and grubby sports shoes, which are not supposed to be washed in the machines.
Launderettes, mostly based in housing estates, are not the only objects of misuse here.
Cases of shared services being abused are not uncommon. Photos of bicycles abandoned in a storm drain, and supermarket trolleys left behind at a void deck have triggered widespread outrage among Singaporeans.
Still, launderette owners say most customers are civic-minded and only a small minority are not.
Instawash Laundry Services, which has helped more than 20 businesses to set up laundry shops, has noticed some non-customers using their coin wash outlets as eating areas or reading corners, switching on the fans for their own comfort.
At least once a week, mischievous children turn the shops into "playgrounds", said Mr Shawn Chow, the firm's director.
"Some kids would sit on the dryer, or try to squeeze inside the machines. Others would play around with the machine buttons."
The 48-year-old noted that photos of irresponsible behaviour are put up in shops to discourage people from causing a nuisance.
DIY Laundry, which has 40 outlets across the island, has observed similar incidents.
"It shows the ugly side of human nature," said Mr William Lau, 47, director of Styltech Singapore, which manages DIY Laundry. "It just reflects on their upbringing.
"We can't do much as we are not there... and we can't stop them from coming back. If it is just a minor issue, we will just let it be."
There are at least 150 self-service launderettes across the island, up from just 30 five years ago. They cater to foreigners who rent rooms and do not own washing machines, as well as locals.
Rates start from $4 to use a washing machine and $1 to use a dryer for five minutes.
These heavy duty machines accept loads of laundry up to 20kg - twice as much as domestic equipment - though they are not always used for what they are designed for.
Some customers turn up late at night, when the shops are quieter, to wash dusty floor rugs and muddy fieldpacks - ignoring posters telling them not do to. This is despite outlets having closed-circuit television cameras.
Heavy-duty machines are less prone to damage, according to one launderette owner who declined to be named. Each machine is also programmed to carry out an additional rinse cycle to clean the drum before the next customer uses it.
His staff still make visits every day to stop customers from washing forbidden items and look out for improper behaviour, he said.
"When customers know that someone is there watching them, they won't dare to do it."