also some companies have 'train buffet-style' sarnies and pasties etc aboard! still poor value though! when i flew thompson we starved all the way to egypt!
As others we take food prepared at home.Sandwiches pasties etc. Bottled drinks departure side is a lot more expensive. What we did for or younger members of our family recently was take fruit juice in the allowed 100ml bottles and then bought a 1ltr bottle of water departure side and added juice to required taste.