Because most pitchers are RHP's and the Brewers already have enough guys who hit RHP's better. I still don't understand why many are obsessed with getting better against LHP's at the expense of getting worse against RHP's, who are the overwhelming majority. Braun, Aguilar, Perez, Pina, Cain, and Arcia are better against LHP's. Shaw, Gamel (barely), Thames, Yelich, Grandal, and Spangenberg are better against RHP's. Yelich and Grandal are very effective against LHP's, despite it not being their preferred split. Both groups have a balanced mix of dangerous hitters and role players, and they have defensive versatility. The roster is almost perfectly balanced in regard to facing LHP's and RHP's, but should probably tilt more towards facing RHP's because that's about 75-80% of plate appearances. It seems reactionary to want more mediocre RHB's just so you can throw 7 of them in the lineup every time an opponent starts an LHP. They did have a slump against LHP's last year, but I firmly believe that was a fluke. They have plenty of guys who can hit LHP's. Moustakas is a much better option than guys like Cabrera or Davidson. Just listing the players ignores where they'll be playing. Spangenberg should never face LHP. Shaw really shouldn't either, which means it would be helpful to have another bat to face LHP. Although, I did say earlier I wouldn't be opposed to giving Shaw a chance. Plus, if the plan is to bring Hiura or Dubon up at some point, they're fine. Also, keep in mind depending on who the RH bat is, they can be used against RHP as well- so it's not necessarily a LHP only bat.