That is certainly true of some markets, like say luxury cars, boats, fancy rifles, SLR cameras, home accessories, jewelry, clothing; it doesn't work to well in others, say food, commodity electronics, suburban residential property, general home appliances. It depends on whether the product requires extremely high volumes in order to manufacture cost effectively. Take a Nintendo DS for a moment, it has a sophisticated CPU and a pair of pretty fair resolution screens. If I went to manufacture those CPUs and screens, with the idea of only selling a few ten thousands, I'd have to charge many thousands of dollars per unit, just to break even. Rich or not, the upper 20% aren't idiots, and they generally won't spend thousands on just any ole toy; and then at those unit volumes, you, as the manufacturer would have to seriously subsidize the production of games for the platform because the unit count is just too low.
Food, same deal, try to produce quality food for just the top 20%, and you get "Whole Foods" prices, mediocre end user quality (time on shelf too long), and not much profit. Stick with producing grains by the square mile, and the price is lower, but the quality is decent, and the profit / hour is also good.
Or take a refrigerator, yeah, I can put stainless steel doors on it, and some flickering LED lights, and perhaps a readable thermometer, and call it "Elite"; but it still won't sell for all that much more than the generic version with the white doors.. because in the end, it doesn't do anything interesting, it sits there and is cold.
On the other side, say a fancy watch, or home generator system, or that new BMW, or Armani dress, buying a sailing yacht new instead of used, sure, that sort of thing CAN be pushed to gain business from the nobility at enhanced profit margins. Those are good business models, but the NUMBER of vendors who can successfully pursue this will be limited by the total number of patrons. Walmart and Target will fill the need for the rest of us. Is that so bad? The middle class here live so much more comfortably than most of the humans who have ever existed, why complain? Is one harmed by some guy who wants a $40,000 watch? Does the image of a new beamer bother people that much?
Yes we are, as we are,
And so shall we remain,
Until the end.