They are awful characters. Watching them is like watching the worst Cosby show characters. The perfect parents with unlimited wealth who know and discuss every black historical character in history and whose parents were, of course, at Selma. They spend no time with their kids but their kids are all super-intelligent, high achievers at the best private school in New York. The wife dresses like Cruella DeVille in what could best be called, "clown costumes". Not just in the Halloween episode but all episodes. For the Met "ball" episode, Lisa walks ten blocks dressed like she has a globe on her head, with hands outstretched like she's walking the runway, and her dutiful husband carries her train like a dutiful son. I can see how that would appeal to the single mothers watching but married, black men wouldn't comply with the diva routine.
I can see why Charlotte might be friends with her since, as she complained, she doesn't have any black friends but no one else would be friends with this couple.
The 2:02 episode in which the Wexley husband could not hail a cab outside his $10 million dollar apartment required the producers to travel to Eastern Europe to find a white cab driver in New York City. Most cab drivers are black and they won't pick up most black men on the street however they'd probably pick up the obvious millionaire with his two daughters.