You see the Preds removing their weapons and masks to an unarmed opponent, which could be viewd as honorable and/or for the sake of the hunt, so its fairly eas to see both. However, I think Im gonna go with the Hish and say that its for the hunt, because how honorable is it to sit in the trees, with a cloaking device, infared tracking and targeting systems, and a plasma canon and shoot people who dont even know your there.
There could be some sense or honor, but im going with the thrill of the hunt. However in P2 it is clear they have some sense of honor and respect when the elder lets Harrigan go, even give him a gift.