Behind a tram is the safest place in the entire city to ride a bike. Just be careful not so swerve!
Actually on Sundays it is even more crowded because that is a holiday for domestic helpers who have nowhere else to go so they descend upon the city and spend the day - preferably out of the shade - talking, picnicing, playing cards, eating and kibitzing. Apparently, Causeway Bay is where the Malaysian domestic helpers hang out. They are mostly Muslim so that ads a colorful fashion accent to the market scene.
There's a long story behind this that dates back over 175 years to the founding of Hongkong by two Scottish opium merchants, Jardine and Matheson, who were booted from China as a result of the Opium Wars and forced to set up shop on a then-barren rock just off the coast of southern China with the name of "Fragrant Harbor" which in Chinese is pronounced Hong Kong. This was the original piece of land given to Jardine, and the first piece of property that became the colony of Hong Kong.