Some vendors even record themselves digging up the dirt to prove its authenticity.
An investigation is underway to determine the motive behind the father's actions.
The 76-year-old was charged with 13 offences and pleaded guilty.
Tiles usually pop due to changes in weather temperature or age, said MP Alex Yam.
The municipality later sent a vehicle to drain the sewage and assist with the clean-up.
She was last seen in a long-sleeved white shirt, a black hijab, and black trousers with a backpack.
Among those arrested was a 17-year-old boy.
The building involved in the collapse, constructed in the 1970s, may have used lower-quality materials than modern buildings.
A man on the road could be seen barely avoiding getting run over by the lorry.
He said he intended to plead guilty to the charges.