Truly shocking I’d leave an angry letter on the screen or make it my duty to see them when they get in the car
Looking at the type of car I wouldn’t be surprised if it’s a SCROTABILITY car (motability), and they’ll just use the old “I’m disabled” card
Check the tax disc see of it says disabled on it with NIL on the value, not that this should allow somebody to park there anyways but they are a law to themselves!
If all of that isn’t true, then I’d say maybe it doesn’t look like a garden as such like said above