When restaurant professionals working in Manhattan want to unwind with a glass of wine, quite a few find their way to Sanfords restaurant in Astoria, Queens. This 24-hour diner-turned-contemporary restaurant and bar offers many of the same wines they might be selling in Midtown—for much less.

“Industry people are always looking for a place where they can get higher-end wines at an affordable price,” said Chrystl Faye Horton-Friedman, sommelier at Del Frisco’s steakhouse in Midtown and a regular at Sanfords. Ms. Horton-Friedman...