Obviously, this is just an exaggeration of the consequences of adhering to both approaches, but the deeper points are there if you look for them. But this movie doesn't provide the answers, just the stimuli. One fight at a time. We must try to overcome our fellow man one at a time. When you look at millionaires like Bill Gates, you can appreciate the point here.
Dominance takes a while to inititate, but the best dictators have started small.
No shirts, no shoes. This harks back to the primitive man point. Stripping the consumerist wares. Fights will go on as long as they have to. Fincher, throughout his body of work, has had a tendency to do strange things with his characters' heads.