I recall the day on which parking at Matlock Bath Station became Pay and Display. A group of, newly employed I would assume, parking attendants (what is the official title?) were behaving like brainless yobs, bragging loudly about their "achievements" to each other, including "did you see that one, he had his ticket upside down". The small party I was with were a hairs breadth from reporting the obnoxious and unreasonable behaviour to the Council and/or the Press. The staff employed to enforce the parking conditions were so preoccupied with themselves and the "fun" time they were having that the actually failed to spot some excess time parking.
There was a time when there was no need to worry about being pursued for payment when parking in Peak Park or Derbyshire Dales car parks, the only problem being to remember which authority could not act.
As for private companies being employed to run Council car parks would like to see the sums. Is there something about Council staff carrying money though? In any case, paying a proportion of the price of parking to shareholders in a private company makes less sense to me than spending it more directly on maintenance.