The Church has always affirmed that the created world is essentially good, though suffering from a profound distortion and misdirection. What fasting is will necessarily involve us in a discussion of the nature of man and the nature of the world. Fasting is, as the Church uses it, a preparation. Every time we encounter a fast it is prior to a feast. We all know the fast before the Eucharist as preparation for the Eucharist and the fast before Pascha as preparation for the great feast.
All major events require a variety of preparations.
The Church recognizes the fact that part of getting somewhere is the trip and more than the trip, the anticipation. This is a basic human psychological quality. Perhaps children understand this expectation and anticipation best of all. Full participation demands this kind of expectation and preparation. Now, the nature of Orthodox preparations is no mystery.