Interesting thread.
The main reason I fly AA is because they're the only airline to serve our airport though that may change after some major renovations are completed later this year. Since they currently only fly to ORD or DFW from here I'm pretty much hub captive by proxy. Sure I could connect to a different airline there but as a leisure traveler I usually check a bag which means having to collect it, recheck it and re-clear security. Even with pre-check that's a pain. The local AA staff here are amazing and have bent over backwards to help when irrops hit. Honestly I can't remember having a truly horrible experience with AA but I suppose as an occasional flyer the chances are lower that I will than the typical FTer.