ES has said that their approach is "Natives as a strategy not an adversary," I gather that works out to mean. You dont kill the natives just use them agianst your european rival and to help you build up early on.
But If your enemy uses them to kill your people then can't you kill those indians perhaps destroy the indians themselves and bypass the heavily guardedoutpost. Will the Indians be Gia units like the wildlife and just respawn if someone does this? We may just have to wait and play the demo to see.