Maybe because the National league games start at the Top ?? by the time you get to play the American league...you have made your Max amount of Bets ???
I bet more local teams than anything. Easier betting teams you can watch and get a feel for. This year, probably more NL, because the White Sox have no pattern to their play, while i mainly bet the dog in Cubs games.
American league cause I like the baseball overs at thime and the American league has the DH hitting not the baseball tosser! This works for me so this be how I roll!