The holes were created without concern for slope angle or whether there was a drainage arroyo. To me this does not indicate something of secular practical usage. I'd lean toward a ritualistic behavior that had to happen in a certain place, tied with previous performances of the ritual, and performed many times. Question: can they date the holes at either end?
https://imgur.com/gallery/lni-enigma-of-amigara-fault-junji-...