Originally Posted by
intuition
The reason for my thinking is that SK slashed earnings to their own program a while ago. But there are still *A programs that credits 200% on a econ plus ticket, ie you can earn more miles crediting a SK flight to a *A program than to EB.
I have always assumed that there is an agreement between the airlines saying that fare X on airline Y earns so and so many points to airline Z's FFP, and then the rate stays at that level until it's time to renew the agreement, possibly years later.