The way I always told my husbands about Spira was this: imagine a huge monster that can kill entire towns - and does - on a near daily basis. The only way to to stop it, even for a little while, was to sacrifice a Summoner to it. A Guardian, what Sir Auron and I are, protects the Summoner until the end of the pilgrimage.
... oh my. I don't even know what the macarena is, but I'm afraid.