Pat Sajak must have run short that day, or needed a little more money for Hillsdale College, of which he is apparently chairman of the board, so the bonus round was a little ... harder than usual.
His lack of sincerity when a contestant loses the bonus round was par for the course. Not sad at all that this will be his final round on a show that has made him wealthy, most recently at a rate of $13 million/year.