I am not afraid to say that costs more than we have money for right now. I always explain that we do not have an endless supply of money so we have to pick and chose the activities we do and the thngs we buy. I am a strong advocate of teaching children to budget. Ds is 4 and he gets $2 a week for doing two chores, these are in addition to basic clean up which I expect without being paid for it. When we go to the store he takes his wallet, if he wants something that he does not have enough for I tell him he will have to wait and get it when he does have enough. If he is close we go home and check the price online to see if we can get it cheaper. He likes this and sometimes asks us to do it when it is a rather expensive toy he wants.
When we go to the water park I tell him he can get one refill n our cup and a few jelly beans. When he asks for anything I state if he gets that he does not get the refill and the jelly beans. We never eat at the park, usually I pack a lunch to eat on the car ride home. If I want to make it special we will stop at McDonalds on the way home. I love the snack budget idea and will have to see if there are things I can apply it to in other circumstances.