An article in the Wall Street Journal reported that customers who shopped at Neiman Marcus and other high-end retailers were becoming more resistant to paying high prices for clothing and accessories: High-end [retailers] which raised prices incessantly over the past decade, are learning the hard way that even wealthy customers are hunting for better deals and selection, whether online or at shops run by individual brands. . . . Neiman’s Chief Executive Karen Katz . . . reduced snob appeal by allowing Neiman shoppers to use Visa and MasterCard. Previously, the stores only accepted American Express or Neiman credit cards. 

a. What does the article mean by “snob appeal”? Is there an economic explanation for it? Briefly explain. 

b. Why might losing snob appeal be a problem for highend retailers like Neiman Marcus?