Bebey's song is unlike most Western music not so much in intonation or scale, but in being in a descending mode. I can't listen closely enough to analyze it right now, but it seems to be something resembling major pentatonic in its pitch set, but with each phrase leapfrogging down the scale - no upward stepwise movement. This kind of pattern is very common worldwide. The flute acts like a drone, providing a fixed reference point.

This gets codified in Ottoman music where modes can be ascending, descending, or ascending-descending ("arch contour" in Western musicology). All of these occur in Western folk (sometimes in gapped scales unknown to the Ottomans) which also adds a "down-up-down" pattern oscillating around the tonal centre (think Auld Lang Syne). Though descending is not one of the more common ones.

These patterns are big and obvious, no funny stuff about intonation involved.