As Amazon celebrated its 20th birthday Wednesday with a day of deals, it's worth noting that the online behemoth is often seen as catering to all shoppers—especially those looking for competitive prices and convenient shipping.
But one research group says disproportionately large number of Amazon's U.S. shoppers aren't those whom you would typically think of as needing discounts.
"Americans with money—and lots of money—are now shopping at Amazon and, as household income increases, so does Amazon's penetration of the upscale household segments," said a new report from the Shullman Research Center, which was based on a survey of 1,665 consumers.
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Seventy percent of adults with incomes of $250,000 per year have shopped on Amazon.com in the past 12 months, compared with 56 percent of consumers with household incomes of less than $75,000, the report said.