Your KFC is doing well at the expense of more expensive restaurants because Americans really do eat out more than we did as kids, Rich, and the impulse-buy urge as you are driving by the fast food location is clearly very powerful.

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And the end of each aisle - the "impulse buy" space - is also stacked with cans of lager and cider, so selecting and purchasing alcohol is just part of the weekly shop rather than something that we have to think about doing.

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Finally, it helps that books are quasi commodities -- there's no need to try them on before you buy -- and that they're small-ticket, impulse items that are easy to ship.

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And he said that Apple, through its iTunes and Apple stores, had access to a hundred and twenty-five million credit cards, which would make it easy for consumers to buy books on impulse.

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