Reminds me of the promotion many years ago from Daz washing powder when "a representative would be in your area" and all you had to do, if he called, was "answer a simple question and show a box of Daz" and you would win £10.
I was about 11 at the time and heard somebody was in our area. I made my mum buy a box of Daz powder (We were Persil people; she wasn't very happy) I waited in as much as I could and gave her strict instruction what to do when I was at school. When nobody was at home I even propped a box by the door so that it was visible through the glass panel. I left a note saying what I thought the answer was and to post the money through the letter box...
He never came.
That marked the start of me becoming a little more hardened and cynical about promises...