Sorry, I'm not Mike Rohde. I kept the story submission the same as his post title on his blog and didn't realize that it would be confusing considering my username here is similar to this guy's name.
Personally, my understanding is that these in-app purchases require you to enter your iTunes username/password. Is that not correct? His 7 year old didn't have the username/password and the app purchases went through without authorization.
There was another article about this on HN. Do you not know what an in-app purchase is and how it works?