I've been observing some gangs tactics this season in the wasteland and feel I should point out a quite obvious fact. Although it may seem wise to cover your land in metal refineries, each takes 25 power to stay online. So if you don't have power stations they'll be staying offline.

Although a metal refinery that is offline may slow an enemy advance, it does not generate metal nor does it add anything to your gangs score. Your structures must be online to count for anything. So the gang that gets all their structures online will be the one with the highest score.