Chestnut, a Northern Californian with a placid demeanor, also stars in “The Good, the Bad, the Hungry,” a new ESPN documentary about his surprisingly complex relationship with longtime rival Takeru Kobayashi. And the ESPN marketing machine had gone into overdrive to burnish the hot-dog champion’s image. They arranged to have Chestnut arrive at Citi Field with his sausage posse to throw out the first pitch and later hand out hot dogs — presumably the nonhuman kind.