The problem is perspective. The road is flat, so what's projected on it will not appear as the same shape for someone looking on it from elsewhere.
No. If you project what appears to be a "zebra crossing" onto the street, it has to appear on the street in the same place as a real zebra crossing for the driver to see it as such.
There are perspective issues involved, but they exist for both the projection and the viewer. You cannot simply project an image of a zebra crossing onto the street, you have to distort it to take the surface into account. And the viewer's brain will take care of the reverse perspective problem, taking the distorted regular striped pattern as seen on the retinal surface and converting it into "zebra crossing" in the brain.
This is one of the reasons why a HUD would be a better solution to this problem. Not only will the info be invisible (and thus not distracting) to outside observers, it is a much simpler problem to manage the perspective and transformations necessary to project the correct data.
Perform this thought experiment. You are in a large lecture hall. There is a computer projector displaying a circle on the screen at the front of the room. The projector electronics have taken the angles into account and distorted the incoming video signal so that the displayed image is a circle on the screen. Now move about the room so your perspective of the screen changes. The image on your retina will change based on your angle to the screen, but your brain will still see a circle.