Tommy's Mexican Restaurant is a homey little joint with red vinyl booths and murals of Mayan ruins. Papa Thomas Bermejo greets customers, while daughter Candy punches the cash register and son Julio presides behind the bar. The roar of ice crushers blends with mariachi brass. The waitress, in a worn T shirt, scuttles about at 78 R.P.M., hoisting platters of sizzling enchiladas.
Hardly the place, one might think, to shell out $350 for a 2-oz. shot of Cuervo Original 1800 Coleccion tequila or savor, as Michael Javaherian did the other night, two small pitchers of margaritas at $115 each. "I'll look...