Many carriers outside the US only credit between 50% and 75% for discounted economy fares on various routes. On the other end of the spectrum, LH's program offers generous bonuses in 100% increments for full, business and first faes paid. I think these are both fair ways of handling the discrepancy between fares paid.

And certainly better than the move just announced by US AIR that most discounted fares will no longer count towards elite status. This is the most disastrous piece of news to hit the FF scene yet, and could have major reprocussions: either in lost business to US, and force them to change, or widescale adoption by other US carriers for their programs. Be afraid, be very afraid!