In my opinion, the airlines have to reward both those who spend a lot of money, at high prices, and those who will fly the same airline, "unless a gun is put to their head". I am one of these. I fly CO 95% on pleasure, yet always manage to get to the highest status (Platinum), despite the fact, that by flying the specials, I NEVER spend more that $3,000-$3,500 per year. Am I more valuable than someone who spends $35,000 a year, or who spends $1,600 like my wife did yesterday to fly EWR-SAT on business? Probably not, but I am a good, loyal customer who can be counted on to fill the empty seats 10-20 times a year, both domestically and internationally, year after year. This is loyalty and should be rewarded. Since the airlines set the rules and say that I should be Platinum if I fly 75,000 miles, I am simply playing by their rules and receivng the rewards they have determined to be appropriate.
I do think, that there should be something, over and above regualar FF benefits that only someone spending over say $35-50,000 per year should receive. Perhaps this could be international perks, or whatever creative ideas a marketing department can develop.
The airlines need to satisify both camps since its the $35,000 flyer that brings in the most revenue, but the loyal FFers like me that fill the seats.