That's OK but thanks for the offer to reconsider.

You seem intent on using a very narrow definition of illegal and that is certainly your perogative. However, IMHO, you are missing the bigger picture. The OP asked if selling miles was illegal or against any policies. Even if I concede your defintion of illegal (which I don't ) and answer "no" to the first part, the answer to the second part is still clearly "yes, buying and selling miles is against airline policy." As a wise FTer once said: YMMV