Originally Posted by
nkedel
Wouldn't common carrier status prevent them from discriminating in this way?
In practice, they are most likely to cut off a travel agent that issuing a lot of hidden-city tickets (or improperly nested tickets, etc.). I've seen the AA form letters (here on FT, somewhere) and they are tailored to the TA audience.
A travel agent advising a lot of clients to fly hidden-city would be seen by the airline as a lot bigger "problem", and I assume there's no common carrier issues with kicking one out of your booking system.
I remember right when I first started traveling for work in the 1990s, our corp TA gave everyone an information sheet about do's and don'ts and guarded against anything that would offend the airline. I remember an agent saying once "They wouldn't come after you, but they could definitely make life hard for us." We did a lot of repeat trips to the same city (long projects), so the main thing wasn't hidden city - it was nested tickets. The TA made sure that the first flight out to a client site was a one-way ticket, with subsequent Friday-Monday roundtrips, followed by a one-way at the end of the project.