In my classes way back in the day my teacher made me harmonize the harmonic and melodic minor scales and said that chords could be borrowed from all 3 minor scales. This got me thinking because isn't the melodic minor only for "melodic" purposes? And if you think about how many other blue notes and non diatonic notes we hear in pop/rock/songwriting music nowadays, well is the melodic minor scale even any use in these genres?
Usually, a harmony or chord that's accompanying a part of a melody - a phrase or just a couple of notes - will reflect at least one of those notes in its makeup. So, if notes from the melodic minor are being used, it makes sense to use those notes to form a harmony.
Melodic minor was used in earlier music, with the ascending and descending notes differing, although the first five in a scale are the same, whether it's harmonic, natural or melodic. And melodic ascending notes are used both ways in jazz!
The big difference is really the 6th note - a semitone higher in the rising melodic than in the harmonic and natural minors.. But that change affects three chords that can be used in a minor piece, giving more options. So, why not?