here was a day I had last year:

Up at 5am, grab something to eat and go to the airport, getting there at 6:30am. Wait 3 hours for flight to leave at 9:30am - too early for lunch, still full from breakfast. Flight was 4 hours - no food or snack available that I could eat (can't have carbs). Storm at new airport, circle for an hour waiting for a clear runway. Flight down, run to connection flight that is ready to take off - no time to get snack. Another 4 hour flight with nothing I can eat on it - now we are working on 12 hours without food. Again, even without my doctor telling me I need to eat at least every 3-4 hours, this is a long time without food for most people. Especially children (think of the children! )

This is not an unusual situation - happens all the time to frequent flyers. Certainly I would be bringing something to eat, as I have dietary restrictions, and cannot count on the airline providing something I can eat. Even the 'available for purchase' meals are likely not going to be low-carb. Or gluten-free. Or dairy-free. Or kosher. Or low-fat. Or whatever dietary restrictions exist out there.