Actually, they do - courts award damages for loss of life all the time, and calculating such economic loss is a basic skill of practicing tort law. A person's life is almost always infinitely valuable to the individual in question, but for everyone else it's surprisingly calculable. A gloomy business, but a necessary one all the same -life still goes on for the survivors, and at some point accountings are made and people move on.

Sorry, but that is not what I'd include in the real world, not in the sense that is relevant to this thread. Economic loss is not the only kind of loss.

Which is why this $500m loss is not the same as 71.43 deaths, even if that many deaths might result in a $500m settlement.

One thing that's important to note is that it's not a reversible calculation. You can't pay 7 million to buy someone or have them killed legally or something like that because that's the "going rate".