Pam Danziger, president of luxury research firm Unity Marketing, conceded that a snooty sales staff is a reality in many stores. But she was highly critical of the message implied by Ward's research, suggesting the study's focus on so-called aspirational shoppers—those who appreciate high-end goods but don't have the income to be true luxury consumers—colored the results.
"Luxury consumers are among the most empowered consumers because of their wealth and ability to pay, and they wouldn't for a moment accept that kind of treatment," she said. "To me, I think it's a huge disservice to luxury brands to lead them down that path."
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In fact, many high-end retailers have spent the past decade or so training staff to be less judgmental, she said. At one store where she consults, corporate myth includes a customer who arrived on bicycle, was mistaken for a delivery boy, and purchased a $10,000 watch.
Luxury stores have also tried to be more friendly in an effort to expand their market beyond the ultra-rich to so-called "HENRYs"—consumers who are high earners not yet rich that might be uncomfortable walking up to the glass counter.
According to Unity Research, "HENRYs" buy 90 percent of luxury goods—meaning being rude "could kill your business and scare off customers that really matter," Danziger said.
—By Bob Sullivan, Special to CNBC.com