Ok - as I have been doing this very flight at all hours of the day for years, I'll bite and chime in here...

Yup - DFW-MCI, not a transcon.

However, I will say that I have, in years past had an "AA snack" on this flight in F. (I believe it was a wrap). Now perhaps that was a catering mistake, or a test, but it did happen. In the past few years, every time I fly the route I still wait to see if something better than the bagged mix is offered. (It never is, but hey - it's like Schrodinger's Snack - it's both a trail mix, and not trail mix until the FA walks out of the galley! )

I think the bigger issue - and this is as it pertains to MCI - is connections. I routinely fly into MCI via DFW from LAX. The more egregious catering decision from AA is that I can get on an early morning 3 hour flight from LAX, in F, and then only have 30 some mins (by the time we taxi and the bridge is extended in DFW) to move three terminals and get to the next departure gate before going another hour to MCI.

It's like AA is daring me to test the speed of the line at BK during a short connection in DFW or otherwise, relegate myself to a beverage only for 4+ hours of flight time moving halfway across the continent.

(Yes, I could bring something with me... yes I could get up even earlier than Ugh-o'clock in the morning to eat on the way to LAX... )

But to the OP's point:

I *have* had a snack on DFW-MCI - but not in over 24 months.
I too *wish* there was a snack on that route.
I think it's not too much to ask for AA to add a snack to such flights (or at least certain flights, like the first of the day - after all it is very much considered a feeder route and at that time of the day - those onward pax have just come off a separate flight which AA thought was "too early" to cater.)

(Course, this is all moot once AA implements my suggestion of MCI-LAX! Any day now... any day... )

Just my thoughts... ymmv.