I completely think it has to do with demographics based on my own anecdotal evidence...
I live very near Detroit, which has a black population of 80%. There is a mall one mile from me. However, I drive 20 miles to a different mall when I go shopping. Why? The mall near me caters to the black population here, because they are the majority of shoppers. The mall I go to is in a primarily white suburb, and caters to their demographic of white middle class suburbanites. The brands, product lines, and even stores are completely different from one another. They both have a Macy's, but the one 20 miles away doesn't carry pepe, fubu, baby phat, or apple bottom, like the one near me does.
Even though it's annoying for me to have to drive an extra 19 miles to shop, I can't fault Macy's (or any business) for wanting to maximize their profits. Although, I do think their training leaves something to be desired if they actually coached that saleswoman into saying what she said. The woman insulted her own race! On a side note, I went shopping at the Macy's near me one day, and two little black girls called me a cracker. I just about died from a mixture of shock and amusement...