“Real Housewives of New York City” star Kelly Bensimon and chef Sam Talbot are doing a poor job of hiding their romance. While they’ve denied being an item, the pair were spotted at no fewer than three parties Tuesday night: at a dinner at Butter celebrating Bensimon’s upcoming Playboy pictorial, at the bash for “How To Make It in America” and at Interview magazine’s 40th anniversary party at Good Units beneath the Hudson Hotel. “I don’t know why they deny it,” laughs a friend. Also at the Interview party were Naomi Campbell, Kate Bosworth and Mary-Kate Olsen.