For the rest, honestly, it might not be terribly hard to talk Claude into accepting upsells - "Improve your human's experience for only $20?" as a required field. Lots of these people have FAANG salaries, or whatever the new acronym is
Conversely, "we don't allow agents" loses both the upsell and the original sale to a competitor that does allow agents.
Competitor's margins also rely on the upsells and ads. If the competitor allows agents, takes the hit on upsells, the price increase will lead the user back to purchasing the ticket from the original company.
Obviously many possible ways it can go, so we don't know.
Eh, I'd give it a standing instruction to upgrade my cabin if the price makes sense.
Isn't that was ITA Matrix [1] is?
but is it load-bearing?