One of the best things about the airlines canceling their food service is the incentive it gave passengers to travel with their own favorite snacks. Some Moms have flight "snack handling" down to an art. They know just when to break out the favorite, or never-before-tasted, treat. Usually it's just before the kid does that Gumby backslide to the cabin floor.
I've always found chocolate a great way to stave off whiny kids and adults alike. It can make travel mishaps that much more tolerable–delays, cramped seating, surly companions, even surlier flight attendants go from disaster to nuisance with a really fine piece of chocolate to enjoy. I discovered the The Chocolate Traveler a few years ago. Originally, the stylish graphic on the package attracted me and the round tin was perfect for travel. I found them while on vacation in Laguna Beach, CA. I still had a flight to "snack up" for, so I grabbed the little round tin. When I tasted a dark chocolate coffee wedge mid flight, I knew I was hooked. They're available at Trader Joe's, not with the cool graphic mind you, and through their website.