I know what you mean and feel the exact same. I took my gran to hospital few months ago with pancreatitis, she was in agony. There is no A&E car park so had to park miles away in the normal car park and further more pay for hours upon end. Last thing you worry about when you have a relative in agony is if have enough change (my hospital doesn't give change nor take notes) for the car park machine, let alone enough for all the hours I was there. My biggest fear is for example a pregnant woman driven to hospital by her partner, trying to get her to the ward to have a baby. What do you do? "Sorry love, I need to go and park the car, pay £2.50 (that's if you pop the baba out in the next hour)...then I'll come back and sort you" Further more, that's if you are lucky to find a place, most times I go to the hospital 9/10 times I have had to drive round and round because majority of the car park is full of staff and in the end abandoned my car near a hedge on a patch of grass because if I don't I get threatened to be struck off the waiting list for not turning up to appointments.
If the fact I didn't have to go straight to work afterwards I was almost tempted to take my Gran. She has a disabled blue badge after she broke her hip and can now only walk a few metres without a stick.
Saying that though every time I have to take her to the hospital for a check up the disabled spaces are always full. It results in me having to drop her off at the entrance and go and park in the normal car park. At least at stafford hospital you get a token which you have to pay on the way out. With my Gran I take her blue badge and the yellow token to a certain place, then fill in a load of paper work to prove that I am related to her and have driven her to the hospital, after which they give me a blue token which lifts the barriers so I can leave without paying.
Shrewsbury isn't too bad as at least they charge you on the way out so you only pay for the time you were there.
I used to keep finding ways around the parking charges but they have all slowly disappeared as the parking company has wised up to them. They put double yellow lines around on the roads that lead up to the hospital, the nursery just round the corner now has a pay and display machine on it and the machine was changed to one of those that requires to put your registration it. I often used to sell the rest of my ticket to someone for £1 to recoup some of the cost as it usually had enough for them to go there appointment too. Either that or if I was lucky someone would sell me theirs.