I'd imagine that Pujols and Mauer are more prone to intentional walks than the others. Keppinger might have been the only other one that I might have eventually thought of, and even then, that's only because of playing fantasy baseball.
In addition, Juan Pierre has 1 more walk than strikeout, and has had more K's than BB's 5 of the past 6 years (equal numbers in 2009). Ojeda is also only +4 and Ruiz is only +5.
I'm not attacking your research or anything Dipre, I'm just showing how uncommon this stat is.