Silencers (suppressors) should not be a rare thing on weapons. They are not often used in the civilian world due to licensing requirements by the federal government and they are outlawed in some states. So why should they not be rare? Hearing protection. It is better for your ears. Add to that, in tactical situations like these riots, it allows you to hear your surroundings better and your comms. Even shooting rubber bullets produces noise.
Makes sense.
And the enemy can’t triangulate on you during subsequent shots.