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.
If you use canned pasta sauce instead of making your own: screw these brands. Newman's Own is way better than all of these and is often cheaper. Bonus: 0 added sugar.
Sugar in many products such as yogurt is not very useful and just added for flavor. In pasta sauce though, the sugar is added in order to cut the acidity. No one buys pasta sauce for its sweetness.