I guess it's pretty much about the competition. Those airlines that BA is competing with directly may only have sandwiches to sell, in which case it doesn't really provide much incentive to offer more in ET.

(Seasonal routes I believe are return catered from LHR and I think there are space issues if they are to use a tray for a hot meal for ET or something like that, as well as issues involved in being a seasonal route?)

CE catering for the likes of CFU is non-standard Band 4 - instead of getting a salad, you get a pudding AND a piece of cheese, rather than a pudding OR cheese.