I, too, was surprised that the dog bit someone. I know all dogs have the potential to bite, but labs are not big on that. Most of my dogs would not just go up to someone for the sole purpose of biting them. But if someone grabbed one of them or got in their face or something -- a couple of them probably would. Then I have a couple that would bite strangers if the stranger were on "their" property. I don't let them have the chance. And some of them would, like Cody, knock them down licking them all over. LOL.
One day I came home and one of my smaller dogs (40 pounds) -- one of the escapers -- had been out of the fence. Two little neighborhood girls had put a necklace on her and had tried to LIFT her over a 6 foot privacy fence. OMG -- I almost fainted. I was so relieved that she hadn't bitten anyone.