Let's see if they start chalking tires in NYC...
In non metered zones, chalking is the only way to detect and enforce. Most violations in metered zones are detectable without chalking.
Where i work where there is a residential restriction they take a picture of your car every time they pass, and it automatically marks the location via GPS, if they come back and the car is still there you get a ticket, they have a map on their tablet where they see every spot on the street and if it's marked that car is parked there.