I am aware, that's why I hedged with poor taste. Nevertheless, there is no way to know if the green outside RC's is just paint or cleverly camouflaged visual cue. On the other hand, we have positive evidence that anchor lock does have a visual cue. A certain visual cue on one side, with an uncertain one on the other still suggests both are visual cues (or Rich just forgot in the case of the office).
Edit: I'm going to add that the inside of the office isn't green, so it isn't that the tower's building blocks are that colour.
Edit 2:
I'm guessing that you've only looked at the forerunners. You also seem to misunderstand the purpose of the category.
Grey Wolf