A second way within the system is that people start to vote for politicians who are serious about privacy.
Give us a kindly king! We've got systemic issues that need to be fixed. What would you say if I suggested a form of government where you're well-being and happiness is contingent on the wisdom and industry of every other person? Yeah, not a great plan - but here we are.
If the license plate tracking gets to that point within metropolitan areas (presumably where cameras are most dense) or they start doing it from blimps or whatever, at least there is precedence for striking it.
It's not going to stop the collection but it should at least prevent the data being used against you in court. Of course, parallel construction. Sigh...