"Emotionally, people are still conditioned to shop," he said. "The ultra high net worth individual is less than 1% [of the population], but their buying power is still 15% to 20% of the market."

But where the wealthy shop may change. The "merely" wealthy will shop at Costco, which has a wide range of premium goods at value prices. But their more affluent brethren will be there, too. Through August, the company has reported a comp-store sales increase of 6% in the United States, though rising gas prices are a major factor in the increase.

"A lot of the very wealthy got that way by understanding how to manage their money," Haddigan said.

The merely wealthy, instead, are looking for value, albeit in a different way from those who frequent discounters. Rather than spending $5,000 on an outfit, the merely wealthy now may choose to spend a comparable sum on artwork, which may increase in value. Major purchases are now seen more as investments than indulgences.

"That consumer is out there and spending, but looking for value-based assets," Haddigan said. "There also is a mindset to have some liquidity, and those assets [such as artwork] do have residual value."

Not surprisingly, the retail vacancy rate is rising because of both high construction levels and recent tenant weakness, Marcus & Millichap notes. The company anticipates at least 7,000 store closings this year. However, some sectors, such as grocers and pharmacies continue to do well. Rite Aid's difficulties are due more to its capital structure than sales, Haddigan said. Restaurants other than McDonalds (with comp increases of 3.4% in the most recent quarter) are "being beat up badly."

That doesn't necessarily affect the ultra-rich. But those who wanted to feel that way are cutting back.

"This is a question of discretionary vs. necessity," Haddigan said. "And a lot of the discretionary is slowing down."