retrochic is right. Eddie, you are needlessly taking the space of somebody who needs the disabled parking. You don't, you are fit and able.
That is why there is a photo on the badge. If a warden sees you getting in or out of the car and asks to see the badge you could get a FPN as the disabled person is not with you.
Who Can Use the Badge?
The badge is for your use and benefit only. It
must only be displayed if you are travelling
in the vehicle as a driver or passenger, or if
someone is collecting you or dropping you
off and needs to park at the place where
you are being collected or dropped.
Do not allow other people to use the badge
to do something on your behalf, such as
shopping or collecting something for you,
unless you are travelling with them.
• You must never give the badge to friends
or family to allow them to park for free,
even if they are visiting you.
I do get what you are saying about using the car for the benefit of the disabled person but that does not entitle you to use the badge if that person is neither getting in or out of the car at that place. I repeat, from the conditions:
if someone is collecting you or dropping you
off and needs to park at the place where
you are being collected or dropped.
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/206022/blue-badge-rights-responsibilities.pdf
Of course, hospital car parks are private land and may have different rules.