Okay, so lets move back to a driving metaphor, since you seem to prefer that.

If you drive in the US, the contents of your car are somewhat protected by law. It's not trivial for authorities to obtain the right to search your car, though I understand it's common for some to flout the rules and search anyway.

But there are not gates on the highway which scan all cars and subject the contents of all the cars along with details of the drivers to government scrutiny. Not just the number plates, everything in and about the car.

However, it is the goal of several agencies to perform this level of searching to all data transmitted. Why do you claim that people have less right to privacy when transmitting data in the virtual vs the physical world?