Down the 7-mile stretch of white sand on the Gulf of Mexico, waves lap and sea oats sway in the dunes. Two bridal parties and a few dozen tourists assemble by The Sandbar lounge/restaurant for Anna Maria’s nightly rituals: sunset weddings and guessing which minute the red orb will drop below the horizon. The Sandbar winner typically gets a bottle of Champagne (dessert or T shirts for teetotalers). Unlike...