I just took a look at http://www.aa.com/content/travelInfo...lService.jhtml

Here's what it says about domestic first class meal service:

"First Class Complimentary Food Service
Complimentary food service is offered in First Class on all markets systemwide that have flying times over 1 hour and 45 minutes and operate within traditional meal (breakfast, lunch and dinner) windows. Generally, a snack service will be provided on flights greater than 2½ hours outside meal windows."

I guess the key word is "generally." It gives AA the opportunity to go snackless on some routes, even on flights greater than 2½ hours.

Also, during "traditional meal windows," they specify flying time, not scheduled time. The line about "flights greater than 2½ hours" does specify flying time or scheduled time.