Ian Walker has an interesting take on this:
"..car parking is a nice illustration of the bizarre level of freedom given to motorists..
..here's the question: why should I be allowed to own a car if I have nowhere to store it? I am not permitted the same freedom to store anything else on the road. If I own a caravan, or a speedboat on a trailer, I am obliged to have off-road storage facilities for it. If I want to place a skip outside my house when doing building work I have to take great care that this hazard is brightly lit and removed as soon as possible."