Outside, dozens of protesters picketed against his alleged bribery scandal, worker pay and treatment of animals.
Bloomberg LP President Dan Doctoroff had a quip that revealed just how much New York hates Walmart.
"First off, congratulations on making it through the enthusiastic crowds outside," Doctoroff said to Duke before his hour-long interview. "I think that the last person who had this warm of a welcome was (Muammar) Gaddafi."
The now-deceased Gaddafi was controversial because Westerners disapproved of his leadership in Libya and called him a dictator.
The protesters and subsequent joke show that America's biggest retailer is still hated by New York.
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