I'm watching through the Matt Smith episodes again, and there's this plotline about Amy cheating on her fiancée (Rory) with the Doctor, and everyone is shocked to learn she kissed him...

Except in the first episode, it's established that she works as a kissogram, so her kissing other people shouldn't be surprising at all?

Like, they write her as having BOTH an openness to kissing others AND a closed relationship to kissing, and that makes no sense