simple reasons why i kill them, they annoy me, that's it .... well they are often caught in the cross fire but i don't think that's justifiable
and im sorry, but sometimes in real warfare ... sometimes your not just killing a man, sometimes it could even be a woman or a child with an ak, there only intention is killing you
I think you cant get 100% on fallout 2 anyway because some quest shut others off due to others
in the end, you will have to pick sides and you cant help everyone
(im going to stop now)