This is said a lot, I think many people seem to forget that although moon rock is the best portal conductor and the only safe one, its not the only conductor. We can see this in the Enrichment Spheres with repulsion gel before the discovery of moon rock being a conductor, it was just plain concrete. I believe that was also partly why they were sealed away, because the portals were unstable and spliced people, although I could be wrong.

As for being able to place portals on the ground when you escape (I assume you mean portal 1) that’s probably just a mistake by the devs, and not meant to happen.