The history of how cars came to 'own' the road is an interesting one. There's more to it than you might imagine.
The full story can be found in this article: The forgotten history of how automakers invented the crime of "jaywalking"
It describes how as cars became more common, pedestrians were demonised and made to appear stupid if they continued to walk in the roads (as they had done for centuries).
Which brings us to the modern day, plus a bit.
Should the perhaps ambitious dream of full automation be achieved, pedestrians will have the option to share the roads with cars again. Not deliberately, but once mischievous schoolboys realise that strolling out onto the A46 will result in all the traffic grinding automatically to a halt... why bother with zebra crossings?
Take that mischief a little further and there's a world of pain awaiting owners of autonomous cars.
Aside from schoolboys and car jackers halting your car on a whim, how are we going to cope when the 'smart' car at the front of the queue suffers some malfunction - when it's empty?
There's already much talk of cars being 'summoned' so there won't always be a driver to take responsibility when your Tesla-Benz conks remotely.
The first autonomous cars are going to be expensive. Wealthy early adopters will kick back and enjoy being chauffeured to the office in style.
They won't however love the idea of hungover proles eating McMuffins in their vehicle, so far from sharing, they'll be sending their shiny new autobots back to the 'burbs to park up for the day.
That's potentially a lot of cars not being shared yet occupying valuable road space - whilst empty.
The dream of mass car sharing might one day become a reality, but before that be prepared to see our roads congealed with empty cars shuffling back and fore at the whim of their masters.
Are you looking forward to sitting in a traffic jam on the M4, gazing around and realising you're the only human in sight?