My ex used to work next door to a 1-hour photo place. She would get her film developed there all the time and knew the guy behind the counter fairly well. One time I had her develop a roll for me. When she brought it home, I showed her one of the pictures from the roll (below). She had thought I was taking it with the digital, but I swapped when she was distracted and took it with the film camera
She was very embarrassed knowing that the guy next door to her work had seen her like this!