Are you kidding me? They make it extremely obvious. Apps with in-app purchases have a giant message on the App Store that, upon clicking, brings you to a list

Are you kidding me? They make it extremely obvious. Apps with in-app purchases have a giant message on the App Store that, upon clicking, brings you to a list of things the application has for sale. Not to mention there's a restriction on iOS devices that allow you to turn off in-app purchases all together. It's like blaming Comcast because your child purchased expensive pay-per-view material when you could have easily blocked the channel.