You are reading a single comment by @Nef and its replies.
Click here to read the full conversation.
-
Strategically placed ANPR cameras. Because of railways and such it's impossible to make all but short journeys without crossing a fairly small number of pinch points.
The goal is to make regular drivers switch vehicles, so it's not a problem if some journeys aren't picked up, or if a minority of drivers figure out where the cameras are and aren't.
You only have to pay on days you drive it. For occasional use cars it could make sense to just pay rather than swap it.