I guess if you just look at the first ingredient but its both obvious there are multiple sources of sugar/simple carbs and that jam is typically very heavily sweetened; this is how it has a long shelf life.

Jam is a pretty sweet product, but that doesn't mean I'd expect I'd expect more sweeteners than fruit. A basic recipe for strawberry jam might require a couple pounds of strawberries and a couple cups of sugar. That'd still have a shelf life of a year or more (unopened).