With all the Automatic Number Plate Recognition cameras around that's a risky strategy in the UK. Perhaps he just puts it on in France.
Or the owner doesn't live in the U.K. so if picked up by cameras on the continent, do they bother to get in touch with other countries? I know it is often said it is too much trouble here when trying to trace a foreign reg. so it doesn't get chased up. It seems only the people who play by the rules get done most of the time. And we end up paying to cover the costs of those that never pay.

We've received so many letters at my block of flats from banks, mobile phone companies, power companies, and debt collecting agencies for huge amounts (many thousands of pounds) for people who've rented and lived in one of the flats for a short time, never paid their bills then left the country and gone back to Europe! I have another recently arrived with over £3000, just for London traffic offences! (parking and/or wrong lane or speeding caught on camera probably)
It takes time to run up that much of a bill - how come they are never caught? Since the windscreen tax disc was abolished here, they have lost millions! So much for it saving money as was predicted!
Roy