Holiday travelers walk through Chicago airport

December 26, 2012 | 7:49 p.m. CST
Travelers walk to a ticketing desk Friday at O'Hare International Airport in Chicago. For many passengers, air travel is only about finding the cheapest fare. But as airlines offer a proliferating list of add-on services, from early boarding to premium seating and baggage fees, the ability to comparison-shop for the lowest total fare is eroding.

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