Criminals are part of the general public(unfortunately) but I see your point.
If people think the ANPR cameras are only about motoring offences then I'm afraid they're sadly mistaken. The following two examples may help illustrate this.
1)A man was seen to be bundled into the boot of his car and driven off. His family saw this and told Police they believed the asaillants intended to set fire to the car with the victim still in it. The details were put onto ANPR and the car was picked up in a neighbouring force area by that system.
Using the force helicopter, plenty of local knowledge and a lot of hard work, the car was intercepted and the victim released. On the back seat of the car were a couple of 5 litre cans of petrol and a pile of old newspapers.
The men were later convicted of kidnapping and conspiracy to commit murder.
2)A woman was walking back to her car at a Motorway Service area when she noticed a number of Asian men gathered round a car and a van. On the bonnet was what the woman recognised as a map of a British airport. She recognised this as she used to work there.
As she drove out of the service area behind the two vehicles, they drove in the direction of the said airport. She used her phone to call the Police at the airport and reported what she'd seen and where she and the other two vehicles were at the time. After about half an hour the Police told her to break off and let them get away.
They then used ANPR to check that not only were the suspect vehicles where the woman had said, but that she was indeed following them. PNC revealed one of the registered keepers was known to Special Branch. What the investigation revealed was a link, perviously unknown, between both the men.
Eventually the vehicles carried on past the "target" airport and went to their home addresses. That car and van will now be on the ANPR database and because of the link between the two males so will any others linked to them.
Revealing the location of ANPR cameras will be a disaster in far more ways than just letting the Cops know if someone hasn't paid their Road Tax or insured their car.