That is something I’ve never encountered anywhere except bridges. Just because there’s no road there doesn’t mean you can’t walk (unless the space next to the road is air/water).
To be clear, the technicality I was excluding was the 'technically you can always walk on the road' part. In places without footpaths your choices often require walking on the road because of fences etc. even if momentarily that's still a horrible walking experience that will effectively cut pedestrians to zero. Also, gigantic highways across which the crossings are separated by kilometres will effectively segregate areas from anyone who has no car.