Of course the vast majority of "spys" are balding 40 year olds that drive their import car onto the enormous parking lot of the NSA and walk inside to massage data in a disjunct ecosystem of Java CRUD applications and the occasional "runs best with IE6" website.
Trackers are far more useful as supplemental collection devices against targets: where are they going, uphill or down, are they nervous when crossing a border, etc.
