Yet students at Hang Seng Management College, in Siu Lek Yuen, were unhappy about what they thought were "one-sided" portrayals. So they produced four short dramas, collectively known as Northside Story, to offer a different perception about these incidents.
Their performance - part of a Theatre-in-Education programme co-organised by independent drama group Theatre Works at Hang Seng - premiered at the North District Town Hall last month. It will run again later this year.
One drama, Trading Like Locusts, looks at the transaction process of parallel trading in Sheung Shui. It was based on observations and interviews carried out by three student actors.
"We've heard about the booming industry from media reports, but few are able to understand or visualise how exactly it works and why people want to become a trader," says student actress Venus Chan Nga-ting.
The play opens on a typical morning - traders flood the train station and nearby road, as they pack bags with goods to be sent to pharmacies across the border.
Some traders commute back and forth three times a day, and earn up to HK$700. They can earn HK$1 for carrying a bottle of vitamins and a few dozen dollars for electronic devices, such iPhones and iPads.
The Hang Seng team found the goods ranged from local teenagers' favourite drink, Yakult, to live lobsters stored in tanks. "It is prohibited to take animals over the border but the traders are fearless and willing to break the law," says teammate Kingsley Wong Kin-sing.
Traders come from many backgrounds, and they include elderly women, housewives with children, and students.
"It's as if parallel trading has become a part of the community's daily life - a job without an official appointment letter or the need to pay taxes," Venus says. "They're like hawkers."
Team member Steve Wong Shing-chau says demand has been fuelled by deep-rooted fears over mainland food safety. "Traders buy baby milk powder to be sold in mainland pharmacies because their customers trust Hong Kong goods."
By chance, three other students met Raymond, the son of the psychiatric patient from Choi Yuen Estate, who has been detained over the security guard's killing. In their drama, Blessing In Disguise, they portrayed his sad story to highlight the impact of mental illness on families.
According to Raymond, his father had been suffering from hallucinations since childhood when he saw his grandfather being beaten to death.
Then he lost his savings after working as a taxi driver for many years. To make matters worse, he did not take his medication regularly, and his family was too busy to care for him.
They pretended to lead a normal life and rarely discussed the man's condition, which gradually worsened until he lost control on that fateful day.
Student Bess Lee Ka-yan says that a big part of the problem is that psychiatric patients living in the neighbourhood do not always get all the help that they need.
Bess says: "If society offered more care and resources to these people, such tragedies could be avoided."