You have to have an insurable interest in the person being insured - in the examples Eddie gives the interest is the commercial contract between the advertiser and the insured.
A husband and wife have an insurable interest in each other, as do business partners.
I am confident that Prince Philip will die within my lifetime, but as there in no insurable interest I could not take out a life assurance policy that will pay out to me on his death.
My neighbour is over 100. I couldn't take out a life assurance policy for her, either.