I suppose you've got a point...
I personally converted to clip folders from my leatherman because I discovered that extra sheath hanging on my belt interfered with things I normally did (like getting in the car or a small seat).
So because of that I sometimes operate on the assumption that others share my attitudes, but I see now why you would carry it sheathed.
Not sure if you are aware but if you are really desperate, Benchmade sells generic nylon sheathes for their knives, I know you said Kydex or Leather, but these are the only sheathes I know of for benchmades.
Good luck.