That's true if you define modern policing as a form of mass surveillance, but doing so stretches the dilutes the usefulness of the term. People see a difference between automatically flagging cars on a stolen car hotlist, and monitoring the comings and goings of every resident in their town. And they're right to see that difference, and to roll their eyes at people who don't.
That doesn't mean the cameras are good; I think they aren't, or rather, at least in my metro, I know they aren't.
These cameras may have been originally sold to municipalities as a way to find stolen cars, but from one year to the next, federal agencies have (1) decided that their main goal is finding arbitrary noncitizens to deport, and (2) that they're entitled to the ALPR data collected by municipalities in order to accomplish this goal. The technology isn't any different, but as a result of the way it was deployed (on Flock's centralized platform), it was trivial to flip a switch and turn it into a mass surveillance network.