A massive number of Top Grossing games use this model. Just looking at the Top 20: Tap Zoo, Restaurant Story, FarmVille, Kingdoms at War, Touch Pets Cats, Zombie Farm, We Rule.<p>I suppose there should be a setting (perhaps even the default) that allows parents to always require a password for every in app purchase. Wonder how much it would affect sales...<p>What's funny is I bet that most people who complain about "expensive" (read: more than $5) apps wouldn't blink at spending a bunch of money on virtual coins/berries/gems/stars/whatever.