Well, when the owner is paying, they make the argument that the "recommended practice" is to replace the rotors too, since it is probable that the rotors will be under spec by the next time the pads wear down to trip an error or need replacement.

Ask them if they will inspect the rotors for free to ensure they don't go below spec.

Personally I replace parts when they are worn- rotors, pads- and I inspect them independently. But I do find the policy on this to be someone elastic at BMW, depending on who is paying and who is writing the work order...

A