They should think themselves lucky they are allowed to park at all.
Who needs their nasty, filthy machines cluttering up the place?

"Motorists will not celebrate and even the staff of Westminster
council's formidable parking department have not planned any official
ceremony to mark the day. It will be left to historians and the
employees of a few “parking management solutions” companies to find a
suitable act of revelry with which to solemnise the occasion.

For today is the 50th anniversary of the parking meter. Mayfair
residents awoke half a century ago to find their pavements had been
planted with 600 of them, dials poised to measure the minute with
unforgiving accuracy..."

More:

http://www.timesonline.co.uk/tol/news/uk/article4305536.ece