Well they are banks and ditches. So I suppose you must be unhappy with the ceremonies bit. But ceremonies is quite a vague / all-encompassing kind of idea? Am I right in thinking that the insides of (ordinary) henges are usually very 'clean' with hardly any finds like wot you'd expect anywhere else? (I might be wrong) And they're not full of burials. And they're not usually places people lived (going by the finds). So isn't 'ceremonies' actually quite a good catch-all for whatever else you might do in them, presumeably something unusual or special? Even a football match you could call a ceremony if you stretched it far enough.