Every time I go to Europe, I'm reminded that although in the US many people think of Europe as one place, there are major cultural differences between countries. The US, while one country is quite large and quite diverse. The differences are not based on a national boundary, but by regions, but the food and tastes of New England are markedly different from say the Southwest.
That said, some of the processed bread I've had in the US bears little if any resemblance to anything I've seen in Europe and I can see how it would not appeal to a European palate. If I hadn't grown up with it, I probably would find it extremely unappealing too.
Jello salad was very popular in the 50's to 70's and still seems to be common in mid-Western and South Eastern potlucks. A savory Jello salad, if there is such a thing, is lemon or lime Jello with vegetables like carrots, celery, peas, etc. suspended in it. It is often served on lettuce, garnished with radishes, and may include a cream based dressing like French (mayonnaise and ketchup mixed), Green Goddess, or sour cream. The sour cream could be mixed into the Jello too. In the 50's and 60's there were savory Jello flavors like Italian Tomato or Celery, but they were discontinued. I can only hope the salads were better with those, since a sweet lime Jello, crunchy vegetable, and cream based dressing is not a combination I like.
A sweet Jello salad could be any flavor with fruit suspended in it, often canned fruit cocktail. Cool Whip is a preferred topping. A sweet Jello salad seems to make more sense to me, since it's at least all consistently sweet and dessert themed. It is worth pointing out that one would never confuse the flavor of Jello with that of fresh fruit, although some flavors are better than others.