The death of diner culture has been predicted for years, but there’s still some life remaining. : Louis Gritsipis insists he will never sell his diner in Hell’s Kitchen, although developers have had their eyes on it for years. And why should he? “This is my palace,” he said after a recent lunch service at 42nd Street Pizza, the old-school Greek diner on the ground floor of his four-story, white stucco building. People come for pizza by the slice, or choose from the 220-item breakfast-lunch-and-dinner menu.