When electricity first came here, dos Santos says, the utility charged a flat rate to entice people to go on the meter.

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That seems to exempt long-distance service that is charged at a flat rate per minute, as most is these days.

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To process the payments, businesses must rely on third-party merchant service providers (MSPs), which offer a dizzying array of rate structures that range from a flat rate to a percentage of the amount charged to the card.

FORBES: Written by Robert Ziegler