What was the context of the at-bat? What inning was it, and what was the score? If it's early in the game, bunting only puts Dunn (and his speed) at first base. It also sets up a prime double-play situation. The Sox would still need at least two hits to drive him in, so why not let him swing away? If it's late in the game and the score is close, if Dunn successfully bunts he's going to be pinch-run for, which could be a problem if that spot in the lineup comes up again. Fairness in conversation - I'm strongly biased against just about every bunt if it's not done by a pitcher.