Consider buying perishables like milk after clearing security and asking a flight attendant to put those items on ice. Or bring something like Parmalat or Horizon Organic’s eight-ounce low-fat milk boxes, which can be stored at room temperature until opened. For more tips on foods that travel well, see the June 22 Practical Traveler column, “Pack a Picnic for Your Next Flight.”

Does It Have to Be This Way ?

For Americans used to domestic flights, the first taste of a foreign airline can be a head-turner. Eric Lorge, a media studies professor who regularly visits Los Angeles from Europe, was flying American before he tried Air Tahiti Nui from Los Angeles to Paris with his wife and three children, all under the age of 5. He liked that they would often get priority boarding as a family, but what won him over was the way the flight attendants handled his daughter when she was sick. “They kept bringing warm washcloths and water and asking if we needed anything.” His experience with United States carriers? “I try to avoid them if at all possible.”

Not all foreign airlines roll out the red carpet for families. In 2004, Malaysia Airlines banned children under the age of 2 from traveling in first-class sections on its Boeing 747 jets. Next year, when it is expected to get the first of its Airbus A380 superjumbo jets, the airline will extend the ban to them as well. But the services offered to families by most foreign carriers, which include baby sitters in waiting areas and automatic 25 percent discounts (see accompanying article), far exceed those offered by American counterparts.

To be sure, a handful of family courtesies remain on domestic flights, including checking a stroller and car seat at no charge. Children under the age of 2 can fly free on a parent’s lap within the United States. And most airlines will allow children to sit in an approved car seat if there is the space for it onboard. On overseas flights American carriers tend to offer families more amenities — bassinets for infants, pillows, blankets and the occasional child’s meal — because they are competing with foreign airlines.

But why can’t all flights within the United States strive for those foreign flourishes?

“It comes down to one thing, and one thing only: cost,” said Mr. Harteveldt, of the Atmosphere Research Group. “With travelers so focused on saving money, airlines simply can’t afford to offer the amenities foreign flag airlines offer. In addition, U.S. airlines have higher labor costs than many foreign-flag airlines, leaving them with less margin to offer kid-friendly amenities.”

Some travel experts believe that airlines are missing an opportunity by not catering to families. Joanne Gardner, owner of the Travel Specialist travel agency in Wheaton, Ill., said nearly half of her business was planning family vacation. She estimates that 25 percent to 35 percent of her clients actively avoid flying. “People really dislike the whole experience,” she said, from the baggage fees to having to bring on their own food. “Clients are preferring to take trains, rent a car or drive on their own.”

So far, this doesn’t seem to have the airlines worried. Only a few airlines track the number of families flying with children. Those that do say they haven’t noticed any change. “There’s plenty more passengers where you came from,” said Mr. Boyd, the Colorado aviation consultant, summarizing the airlines’ stance: “We don’t have to fight over it right now.”