Fox News: Those airline fees fliers pay to change reservations and check-in baggage really add up. According to data compiled by the U.S. Department of Transportation, fees charged in 2010 brought in $5.7 billion in revenue. The fees were introduced in 2008 to offset increasing fuel costs and the downturn in the economy. An industry trade group, the Air Transport Association, says the fees made it possible for the struggling industry to turn a profit.