I have no idea... As a vegetarian, I always take my own food. Don't want anything with sugar, either, or white flour - well, nothing with wheat, really - so there's nothing left to eat! Except, sometimes, strawberries.
I do find that they often overcharge on drinks, too. £1.50 for a teaspoon full of instant coffee with some hot water is a bit much. So I take my own flask, too (should have decaf, anyway - and try getting that anywhere...)