While some children quickly learned how to save up an allowance for major purchases, most kids learn a more immediately-satisfying method: Spend your allowance on whatever you want to buy right now.

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Once an airline exceed its allowance, it has to pay to buy extra permits.

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The allowance could only be spent on primary care and the patients could buy up to higher priced practices if they saw value worth purchasing.

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They were given an allowance and taken shopping, the only restriction being that they had to buy food with clearly marked nutritional content so the researchers could properly measure it.

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