I'd almost bet they sell 100 M8000 to every M6000. Buying in quantity counts sometimes, is my guess.
I actually had one of the first of these installed on my 84 Trooper. There were Sammies and other small 4x4s in that era these fit well. In almost any other case, you'd want something bigger and there are few vehicles now that a M6000 is really the best choice.