BBQ sauce is full of sugar. Ketchup too. People dip their fries in ice cream. Chocolate dipped pretzels work on the same principle. As does candied bacon and apple grilled cheese. Your Thanksgiving Honeybaked Ham is glazed in a sweet sauce. Turkey and cranberry sauce are a match made in heaven. Bacon and maple syrup were practically made for each other.
For example, this pasta sauce has sugar in the American version (https://www.classico.com/product/00041129077023/italian-saus...) but not the Canadian one (https://www.kraftwhatscooking.ca/brands/classico/product/cla...). The funniest thing about it is that the Canadian version still says "Product of USA" on the jar, they just cut out the sugar for that market.
Some of the local foods in the US also have off the charts levels of sweetness, such as southern sweet tea and sweet potato casserole with marshmallows. Bread and pizzas also tend to be on the sweeter side in the US.
Sugar is not uncommon in commercial pasta sauce, even in Canada.
> That's super reductionist... [list of American foods (or foods that aren't american but are extremely popular there, as in ketchup) with sugar added to it]
You didn't do much to dispell the idea that this is an American thing.
Maybe salted caramel pralines. But sour and sweet is a common flavour trope in much of the world. e.g. lemon + sugar e.g. in cannoli; tamarind and cane sugar in SE Asia and Mexican recipes; Chinotto.
But after a few days in America I wasn't that surprised. It was just another thing with added sugar for no reason.
That is not normal, and it isn't fair to extrapolate your single experience to be so.
I've had hotel breakfasts in 48 states. Nobody puts sugar on the sausages.
You probably had pancakes on the plate and some of the sugar got on the sausages during sprinkling.