not sure if the iOS has a proper file manager now but with those games, you can generally get extra credits or food or other crap by finding the save file, then using one of the many free hex editors, then fins the values of the food and just give your self a few million of them.
I have seen some games targeted at kids where they will charge like $20 for some virtual food, and that is a single player offline game, how many berries your character eats has 100% no effect on the company that made the games.
Those parents should have removed the credit card info, then handed the kid a computer and a hex editor and tell him to make more food instead of buying it.