Back when I lived in Arizona and used to visit family in PA regularly, the gate agents used to make announcements (at both PHX and PHL) about the length of the flight, the limited BOB (buy on board), and that they would recommend bringing food onboard yourself.

I haven't flown a long domestic since moving to the Austin area. Do they still make these announcements? I know I've brought food on. Even at AUS (and at PHL too) there are multiple vendors near the AA gates, many with online ordering options (mostly eliminating the line).

Any food you buy at the airport will be far better than whatever you can buy on the aircraft. Heck, I'd argue that most of what you buy at the airport is probably even better than the F meal onboard. I've sometimes planned connections at ORD specifically to pick up from the Rick Bayless restaurants.