The Centurion Card is reasonably attainable. $150,000 USD is a fairly low threshold to meet for a card that many feel is the epitomy of prestige. You can easily funnel business expenses on your card to meet the spending. A good example is average consumer, "Construction Joe" who just purchased $150,000 worth of equipment for his business. Guess who's getting a "super elite" black card if they want?
Anyone remember that Floridian 17 year-old with Dell PC expenses? He doesn't exactly symbolise the VIP lifestyle yet he has the card. In other countries I've heard of tales where users have acquired the card with very little spending. The card isn't exclusive nor a status symbol.
Additional/secondary cards also dilute the rarity of the card. Members requesting cards for their maids, kids, friends and spouse means more black cards in force. The more Centurions issued, the less exclusive it becomes. Besides, I'm sure AmEx is dreaming up the next card level, and Centurion will eventually be where Platinum is today. In the hands of anyone willing to pay the fee.
Obtain the card for the value, and amenities - not the status.