@cicerone imposter,
Part of it is due to it not being about a specific statement.
--- My doctor said that I need to improve my eating habits.
In this case I have a specific thing I am refering to, when I went and talked with my doctor about my diet.
--- Doctors say that Americans need better eating habits.
In this case, we are reffering to the general sentiment that in general doctors are currently offering this sort of advice.
In the case of the airline, the airline itself can't speak, it's a group of all sorts of voices, and we are saying that the current consenus seams to be the market is weak.