I heard that the throttle stuck, and he steered into the Fairlane and Comet to avoid going out onto the crowded boardwalk. Guess it happened so fast he didn't reach the key in time to turn it off before it hit. And I heard that both the Comet and Fairlane are both owned by one person.
the coupe was part of a special display of American Graffitti tribute vehicles and this was at the end of the event. The movie stars that were signing autographs had already left the area, but the lane for the display vehicles to leave was clear as it had been blocked off for the line of fans waiting for autographs earlier.