Many of the traffic surveys I've worked on have involved monitoring the traffic around supermarket car parks. That means that my own car often has to be parked there for 12 (or even 15) hours. So I've had to take great care to get to know the people who actually monitor the car parks, in order not to get my own car 'ticketed'.
Policies seem to differ greatly, even on the same car park. For example, at the Asda on the Norwich outer ring road, some parts of the car park are regularly patrolled (with particular attention being paid to the disabled and 'p&c' bays) with a zero-tolerance policy towards anyone who breaks the rules. However the 'bottom' section of the car park isn't patrolled at all. You could park there for weeks at a time without any problems.
While, like you Tiggerblue, I detest people who park in the wrong areas just because they're lazy, I've sometimes parked in a disabled area (without a badge) for legitimate reasons. For example I had an elderly friend in my car, who had only come out of hospital (after a hip replacement) a few hours earlier. We went to a Norwich branch of Tesco, so that she could do some shopping. I offered to do it for it but she insisted on going into the store herself. I got a really foul look from a disabled motorist when I used a disabled bay, but that changed to a warm smile when my elderly friend exited the car on crutches.
Chris