I agree with the loyalty side. However, there is merit to the $$ paid argument which I think all agree on to some extent. The problem with the $$ paid argument is that this person may not be very loyal and the airlines want to reward loyalty.

Now having said that perhaps some sort of reward similar to what the Vegas casino/hotels do for their big spenders. This might be identifying people who spend a lot of money on air travel with any airline. Then an airline might provide special invitations with perks (not elite status)to entice those people to spend their money on that airline. Just a quick thought off the top of my head.