And that buying power has become more robust as the wealth gap has broadened to its widest in the past century. A recent survey by The Federal Reserve showed that average income for U.S. families climbed about 4 percent from 2010 to 2013, after inflation, but most of that growth was concentrated among the top 3 percent of Americans. And the automakers are smelling money.
The S600, for example, brings back the Maybach name that Daimler AG abandoned as a standalone brand two years ago. But the maker quickly realized that even with a whopping 18 different models priced above $100,000, it wasn't reaching far enough up-market.
"There is that customer who wants the next step up, and if we don't provide it we might lose them," stressed Steve Cannon, the CEO of Mercedes-Benz USA.
The L.A. Auto Show also saw the debut of the $270,000 Porsche Panamera Exclusive Edition. And Johan de Nysschen, the new global president of Cadillac, said he envisions the need for adding several models to the line-up that would top $100,000, with at least one pushing close to the price of the S600 and Panamera Exclusive.
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Not all super-luxury brands are gaining ground, of course. Lamborghini has actually suffered a sales dip this year, but Italian rival Ferrari has a several-year waiting list for some models. An internal debate over the company's strategy of strictly limiting production to boost exclusivity was reportedly a key factor in the recent ouster of Ferrari CEO Luca di Montezemolo.
Brinley and other analysts suggest this automotive wealth gap reflects broader societal trends. Low-end buyers, in particular, are struggling financially. But many have also discovered an alternative to make their cash go further: purchasing so-called certified pre-owned vehicles, rather than new ones.
But even in the mainstream, the push up-market is apparent. Ford added a new Platinum Series to the new Explorer SUV it launched in L.A. (As did Chrysler with the updated 300C sedan.)
"We didn't have enough of an upscale version" of the old Explorer, said Jim Farley, Ford's global marketing director. Buyers would load the previous top-line model up and still want more boxes to check, he said.
For mid-range and low-end luxury models, low interest rates and longer loan terms make it easier to move up-market. But makers say the typical buyer for a Mercedes-Maybach S600 or Porsche Panamera Exclusive will likely pay cash. They're also likely to have a household fleet of as many as seven or more vehicles, according to industry data.