Untrue. Riots are not unusual, but are not that frequent either. The tendency it happens is higher during civil uprising or social injustice.
The common activity is protest. Protests are different from riots in the sense that the aim is not to destroy or loot property. Strikes are also more common than riots. We should not confuse the 3.
Parag is another one of the non-Singaporeans who depend on Singapore for a job. He will try to make the govt look good and I don't expect him to be impartial on this one.