[sketchley kid]

Owing to the good response I got from my question on German buttons I am trying another.
Among the recent acquired bits was a Luftwaffe Belt, heavily rusted and cut down in length.
I removed the buckle and the hook and gave them a good penetrating oil soak, this worked and I was able to lift off the rust and then noticed a black finish to the inside.
I realized it was an original spray paint finish and i think that the front had also been black at one time as was the hook end but someone had scraped it off.

My question is this was there any special reason for the black paint?, I'm curious because as a young soldier in Italy I had a similar Luftwaffe belt that was steel finish (it came to an inglorious end down an Italian 'Squat & Crapper)..
..So ideas please..