Technology always finds a balance. For every invasive piece of technology deployed, a dozen ways of defeating it comes out. Usually it's made illegal, but said counter-technology still exists.
Example? Radar guns used by cops.
Solution : Radar detection devices. Active ECM's. (Electronic CounterMeasures, ie jamming) Web sites that report speed traps. People flickering their lights at cars approaching speed traps.
If a car's on-board systems wanna report data to the govt, a clever geek can and will reprogram his on-board system to report what the geek wants the on-board system to report. It will become illegal to do so. People will do it anyways.