Be Wary of Membership Programs
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Believe it or not, the total value of unredeemed frequent flier miles is currently greater than the value of all currency in circulation in the entire world. The reason? Frequent flier miles are harder than ever to cash in. What loyalty programs are ultimately for is convincing you to spend extra money.

"Airline loyalty programs are designed to reward the airline, not necessarily you," says Elliott. Elite status may come with shorter security waits, free drinks, and other would-be perks that you might think would improve your coach flight. But Greenberg says elite status is not at all what it used to be.