If you're pretty technical, it's easy to simulate what the NSA does with your imagination. Just imagine what databases they have, and imaging what you could do in a limited way if you made it your side project. Badabing.
Then a controller could issue useful queries for parallel construction, like "select all avatars who have X in their inventory and who are currently driving in location Y", or how about a bar sting: "select all avatars who purchased more than X drinks at location Y and are driving, but are more than Z distance from their likely destination". Are we to presume that this is not being done? How will society react to the idea of such deep reaching surveillance?
The question I ask is: Is it technically possible? Is it reasonable for one to do it if it were possible (economically)? Then I just assume that it's done somewhere in the world.
It's technically possible to track everyone, it's reasonable that governments would want this ability, ergo a government will have done it.