We weren't robbed of hosting. Even if go with your theory of strictly looking at RPI, we wouldn't have hosted.
The ranking of teams is NOT factored in the rpi. You can have two teams on your schedule with identical 43-13 records. One can be #13 in the rpi, one can be #33. Both have the same impact on your rpi (assuming you won both games), but you should get rewarded for beating #13 in the rpi than #33 when you comparing like teams.