Paper Terrors
I was breathlessly informed a few years back that there would be EU-wide road pricing based on GPS in place by the end of 2015 with every vehicle including kid's trikes tagged and monitored 24/7 by the Evull EU. The respondent had probably seen the same document you're hyperventilating about, a "what if" paper saying "could we do this?" like sixty-thousand other Powerpoint presentations that went nowhere.
If the UK government wanted to do this they've got enough ANPR cameras on the main roads to implement a road-pricing scheme without requiring everyone to fit a GPS tracker on their vehicles -- it's already illegal to not have camera-readable licence plates, after all.