Completely unrealistic reaction to the lesbian kiss

I know it's Hollywood's dream that a teenage girl would smile wide and say "Wow" when witnessing a passionate lesbian kiss by her aunt, just inches from her own face, but no way is that how it would have played out. Pippa's a fairly straight-laced teenager in the 70's -- not 2015 -- who was brought up by her pastor father. If she sees that kiss, she probably reacts with shock and maybe a little disgust. Maybe later she could have been brainwashed by the Julianne Moore character and her friend, but her initial reaction would not be one of pleasant surprise.