Travel Maze: Hungry in coach? Your cash is no good here. Try plastic

Next time you're flying coach on Delta Airlines (DAL), and you want an almond butter and grape jelly sandwich or a grilled chicken gyro, you'd better have a credit or debit card handy. The jelly sandwich is $4, the gyro $8 -- and cash transactions for food will soon be history.

In the wake of the September 11 terror attacks eight years ago, airlines cut their free food service, citing financial woes. We've all gotten used to that. But at least they used to take cash. Now they're increasingly declining to sell food or alcoholic beverages unless you're carrying plastic.