I think Casey was very much like Scott Peterson in that she thought Caylee being missing would blow over very quickly. She didn't count on Caylee capturing the worlds heart, just like Laci did. I think this is because both Scott and Casey don't think or feel like normal people and therefore don't understand the love, grief and fierce desire for justice for Caylee that we all feel, and that many people felt for Laci.
You can just feel Casey thinking she has got away with it during the police interview that took place in that little roon at Universal. Near the end of the tape one of the police officers says something about his bum getting sore from the chairs they are sitting on, and then Casey kind of laughs and goes yeah me too, haha. You can tell she thinks they have now bonded and are all ok and they are going to leave her alone because once she reaches that stage with anyone else it all blows over and is forgotten about. As other posters have already said Casey didn't count on people not believing the lies that came pouring out of her mouth as her family had her whole life.
Listening to Casey on that tape scares the crap out of me.
