Mentally, when comparing prices I added in whether there would be sales and delivery charges.

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But what may seem like a great convenience can be offset by extra delivery charges.

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With the high cost of restaurants, and tips, and delivery charges, cooking at home makes a lot of financial sense.

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Also last year, Citizens Advice Scotland published research that suggested more than a million people living in Scotland were being "routinely ripped off" by unfair delivery charges.

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But will so many delivery options and charges and services confuse the customer?

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Peapod, a subsidiary of Royal Ahold and another major grocery delivery service that reaches New England and the mid-Atlantic as well as Chicago, Milwaukee and Indianapolis, charges similar rates (with a small fuel surcharge) in addition to its free pickup.

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