Years ago the French built autoroutes, for which tolls were payable, they were told by the EEC that the charges were illegal, and they said the money was being used to construct more roads, and so got a derogation. Don't know where they stand now but I do wonder whether the UK government's alleged plans are legal in an EEC context.
In my truck driving days we used the back roads in France where the food was better and cheaper, fuel was also cheaper. The French government slapped weight restrictions on many of these roads which forced the truckers back onto the expensive autoroutes.
Coincidentally, they also put a lot of Truck stops, and Cafes Routier out of business. The same will happen here!
Giok