The Guardian reports on this truly funny story:
When a bunch of people emerged from subway tunnels and told this lady’s husband to stop filming his wife and surroundings with his little camera, the couple understood that something strange was going on. Two days later the French tourist learned what, when she spotted her photo in a newspaper! The homeless man to whom she had given her left-over pizza was actually actor Richard Gere, who was preparing for an upcoming movie role by walking around the streets of Manhattan in character as a homeless man, rummaging through garbage cans for scraps of food.