The latest amenities on offer to travelers at airports are not inside—but out.
Motorists waiting to pick up arriving passengers can now grab a snack or a meal from food trucks parked at a growing number of airport cellphone lots, where short-term parking is free for those who stay with their vehicles. At some airports, the cellphone lot is morphing into a full-fledged service plaza, offering everything from sit-down meals to car wash services.
"Airports have recognized that their cellphone waiting lots have great customer-service potential," said Deborah C. McElroy, the interim president of Airports Council International-North America (ACI-NA.)
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The airport food truck trend started with Tampa International Airport in Florida, which began inviting food trucks to park at its cellphone lot in December 2012 during a curbside parking rule transition. That program worked so well that now a different food truck pulls into the cellphone lot—and to a spot near the terminal—each weekday, with the schedule posted on the Tampa airport Facebook page.
Other airports now hosting food trucks in their cellphone lots include Tucson International Airport in Arizona as well as the Long Beach Airport in California, which has a different group of food trucks monthly during "Truck'n Tuesday." At Cincinnati/Northern Kentucky International Airport, a vendor hauls in a food cart daily to serve hot dogs, bratwurst, mettwurst and nachos.
At Austin-Bergstrom International Airport in Texas, the Twist of Spice food trailer has been serving wraps, paninis and Mexican food in the cellphone lot since January. "It not only provides a food option to cellphone lot users, but also to airport and nearby employees as well as residents," said airport spokesman Jason Zielinski.
After seeing the popularity of these food trucks, other airports are joining in. Seattle-Tacoma International and Phoenix Sky Harbor International airports are among those exploring adding food trucks to their cellphone lots and Sacramento International Airport in California has put out a request for proposals.
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In a passenger amenities survey conducted by ACI-NA in 2012, 56 airports said they had cellphone waiting lots. That number is increasing, but until fairly recently "no one has thought to capture revenue from travelers in these lots," said Ramon Lo, editorial director of Airport Revenue News. It appears no one is yet tracking this source of ancillary revenue for airports, he said.
Not all airports are limiting the food trucks to the cellphone lots.
Sometime this year or next, Terminal 4 (American Airlines) at Los Angeles International will be getting an L.A. Gourmet Street Truck structure built to look like a food truck. "The concept and façade will change every three to four months, with cuisine from the most popular food trucks in Los Angeles rotating so that travelers get to experience it," said LAX spokeswoman Katherine Alvarado.
At San Francisco International Airport, three food trucks park outside Terminal 1 each Thursday, drawing customers not only from passengers and their greeters, but from airport employees as well.
After a positive reaction to a four-week trial period, the airport extended the food truck service indefinitely. "This program is primarily a response to airport employee suggestions, so the airport only collects a nominal fee of $300 per month for this operation," said SFO spokesman Doug Yakel.
Service plazas: Beefed-up cellphone lots
At the end of this week, the Indianapolis International Airport plans to open a service plaza with a Circle K convenience store and 24-hour fueling station offering car washing, automobile detailing and quick-lube services. Next month, the first of two restaurants will open on the site.
"This arrangement provides a new land lease for the airport authority and, after three years, a percentage of gross sales," said airport spokesman Carlo Bertolini. "It will generate a new source of non-airline revenue, which is a critical piece of our strategy."
And on Sept. 24, Denver International Airport will open a 269-space cellphone lot called Final Approach. It will provide free Wi-Fi, a children's play area, indoor seating and restrooms, flight info boards and four restaurants, including a 24-hour drive-thru Dunkin' Donuts.
"Our customers asked for enhanced service, and we are delivering," said Kim Day, Denver International Airport's manager of aviation.
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The cost of the approximately $5.5 million facility at DEN was paid for by the site operator, Pacific Convenience & Fuels, and airport officials said that in addition to generating more than 100 jobs, Final Approach is expected to generate $2.3 million in gross sales and more than $421,000 in revenue for the airport in its first year.
—By Harriet Baskas, Special to CNBC. She is the author of seven books, including "Hidden Treasures: What Museums Can't or Won't Show You," and the Stuck at the Airport blog. Follow her on Twitter at @hbaskas.