pacplyer,
Although I agree with all your statements, I think these guys do have to take some blame here. We as pilots are paid to be the last loop in a very complex system. When all of the contributing factors (which you have pointed out quite nicely) line up, it's up to us to end the chain. If these guys started their day so tired, they should have simply reported unfit. Regardless of state rules, airline policy, etc., we have a duty to report unfit when necessary. Imagine how angry you would be if you got on a bus and the driver kept falling asleep. Who would you blame (bus company, government, police)? I would blame the driver.