Buffets are slightly different between all 3 concourses, but the a la carte menu in A and B is the same. However C has a reduced a la carte menu selection.
Also my pet peeve is that for the past few months, they removed pain au chocolate from the bread basket in the morning and replaced them with apple turnovers (who eats them for breakfast!) - but still print pain au chocolate on the menu. If everyone could complain about this to get them to reinstate pain au chocolate into the basket (they do sometimes make them if you pester them - that is, if the head chef is around) that would be my flyertalk favor of the year

Yes, I realise this is even more trivial that the trivialities of the hashtag firstworldproblems.