You are comparing apples to oranges.
Indeed, Leongsam's reasoning is flawed.
The concept of risk must be tempered by factors like what we can, and what we cannot control.
Majority of people cannot choose to commute on the subway on a daily basis. They cannot also choose to keep their kids at home.
However, people CAN choose not to attend large scale social functions. They can choose to avoid crowded shopping malls and avoid eating at restaurants and fast food joints for the time being.
If it is within your ability to reduce risk, then you should go ahead and do that.
Leongsam's reasoning that many things in life pose greater risk (than the WuFlu virus) is flawed because many things can't be controlled and so that risk is simply accepted.