A/S voters, by and large, are voting for their favorite players, their home town or favorite team players, or players they are generally familiar with. World Series appearances breeds a great deal of familiarity.
The Texas Rangers were coming off of two WS appearances in 2010 and 2011. That's likely why Beltre got move votes than Cabrera in 2012.
The average voter doesn't care about defense, unless it's a player with a "one of the best ever" reputation like Ozzie Smith or Brooks Robinson.