I found a 'recipe' for the bitter orangaide on this site. It does seem to me that it takes a lot of sugar:
juice from 4 oranges, 1/4 c of sugar, 1-1/2 c water
but there seems a lot of other things you can do with sour oranges (same site):
The dried flowers can be used for:
Potporri
scenting tea
Peel can be used for:
Marmalade
Candy (candied fruit)
Flavoring baked goods
In Iran it is also used to flavor boiled rice and vegetables
The fruit can be used for:
chutney
Flavoring sauces, creams, jelly, and honey
The juice can be used for:
Salad dressing - suggested additional ingredients: olive oil, sesame seeds, soy sauce, and coconut oil
Flavoring sweet bread, pancakes, and cupcakes
pickling (the acidity is about equal to that of vinegar.) Suggestion was for pickled onions for tacos and gyros
It seems to be a very versatile fruit.