Not sure what the point of this thread is unless it was posted as a new thread by mistake. Anyway, I ckecked mu food cupboard and see that a well know brand named for a town in Italy, contains only tomatoes and citric acid, while my supermarket own brand contains sugar and salt - why?
Presumably they are used for cooking along with other ingredients and the cook would taste the sauce and adjust according to taste. I know that many people add a little sugar to a spaghetti sauce because they have added herbs - basil, oregano and thyme, one of which ( can’t remember which one) causes wind which the sugar counteracts.
But I would have thought the onions would have a much bigger effect than any herb.