Why should they?
It is pretty clearly stated in FO3 (by the Brotherhood Outcasts) that THEY follow the normal doctrine of the BOS.
Another thing stated (at least in the Pit-Addon) ist that when the brotherhood came through Pittsburgh - on their way to the east - they didn´t care much whom...
"The portion of the game I played frequently had issues with maintaining a stable framerate, and the AI quite often had problems quickly finding the best path while moving."
I really hope they fix that in the remaining time, this was what annoyed me most at FO3.
If you can´t find it on Ebay:
Check this site out: http://www.abandonline.com/gameinfo.php?id=179
As far as I know its abandonware, I´ve downloaded it a few years back and it works fine in a dosbox with Windows XP. Without the manual you´ll have some trouble as the game works like "You...
As Lexx said: there are Robes on the Scribes of the BoS in F3.
And @Stanislav Moulinsky: The recruits in the citadel in F3 wore combat armor or metal armor (not sure which it was exactly) and not power armor. So one could asume they just send their elite in combat (and even they got their...