I was explaining this to my daughter in quite simplified terms the other day- we evolved to taste sugar and enjoy it because finding a sweet edible plant meant we had a source of energy to help us hunt that day. Pretty useful if you’re a hunter-gatherer.
So we seek out sugar. Now we can get it whenever we want it, in much more massive quantities than we are supposed to be processing. Most of us are addicted. I’m not an exception.
I don’t even get why sugar is added. Tomato sauce is already sweet on its own.
My wife and I like to get a local brand because it’s honestly the best I’ve ever had. Each serving (3oz, 85g) is 15 calories.
Removes acidic flavours
It sorta depends on the ingredients you’re working with, some tomatoes are sweeter or more acidic than others. Where I live tomatoes tend to be somewhat watery and lack a bit of intensity of flavour. If I’m making sauce at home I’ll taste a bit and add some sugar and/or red wine vinegar to balance out the flavour.