The concept of asking ravingly mad women abusing hallucinogenic substances for advice on important matters of state may seem strange to most people today. Yet if your predecessors asked the Oracle of Delphi before they went to war, the idea of asking the Oracle before you yourself commit your people to a potentially fatal war for your state, may seem more rational. In fact, it may seem to you and your countrymen to be «the safest thing to do».
How do you reconcile «mad, drugged-out crone» with «safest thing to do»? Well, it's the 1000 dollar question, innit? The heart of the matter is that it provided answers. It was social convention and highly socially accepted to seek these answers. And so no–one really bothered about the quality of these answers, the applied methodology etc.
Now, that was really strange, but a long time ago, thousands of years, in the recently austerity–struck Greece. Surely, we would never find ourselves in a similar situation, here, today? Well, one would hope so. Yet, in real–life, we are perhaps as preoccupied with social conventions and socially accepted ways of getting answers, as the old Greeks were.
It seems that if the issue or challenge is vast enough, we will accept any type of answer from any body of people, no matter their skill levels, ties to vested interests, how political might trumphs scientific right, etc. We have an answer! Might as well have come from the spaced–out Oracle of Delphi.