But baseball is a team game and the team may benefit from best hitters RBI number instead of best hitter getting to bat most often
This is true. However, hitters in the 3, 4, and 5 spots will have artificially inflated RBI numbers by virtue of where they're hitting in the lineup. It's why you often see a struggling cleanup hitter hitting something like .230 but still putting up good RBI numbers. RBI's need a runner on base (home runs obviously excluded) and having your best hitters hit more often creates more RBI opportunities. The net result is more RBI's for the whole team, though potentially less for the best hitters, which is the main reason teams have avoided adopting this strategy en masse. The best hitters want their RBI's and there is a fear in the industry that players would simply go elsewhere if they didn't get to bat in the prime RBI spots.
