Originally Posted by
FlyingEgghead
I suppose the current approach exists because from an IT and planning perspective, it's more convenient to keep the price of a given fare class uniform over the week, and then tweak availability.
And I thought of another possible reason for this: It makes distance-based earning (when it applies) a little more uniform relative to fare-based earning, because the distance-based tables effectively assign a cpm cost to each fare class. At parity, AA is nominally associating J with a cost of 40 cpm, D with 30-35, and I with 20-30.