Ann can get corruption points regardless... but at a certain point in the game, if she has high enough corruption points, it doesn't matter what you told her to do at the bar (stay the same or you should change), if they are high she will be corrupted. And after that point at the bar, you can continue to give her corruption points even on Love route.
But also, TTrick realized he didn't want scenes to be accessible based on these stupid points, so he's started phasing that out and just let people choose what they want.