Remember in school doing magnet experiments? And how if you connect a bit of iron to a magnet, the iron becomes a bit of the magnet. Its as if the magnetic field expands to include the iron; the force lines pass through it to create a bigger magnet.
Here, the same effect "a parking field" applies to cars on the road. Normally a zebra crossing's zig-zag areas are off limits to cars, as they endanger pedestrians. Yet if a car such as the Ford Escort M67OTH parks close enough to those cars that are parked in parking spaces, it too becomes legally parked.
The hard part is getting your car close enough to the other parked cars, without actually touching it. As that could damage your car, and nobody wants that.