Founder here. The internet is full of contradictory statements, but that doesn't mean we can't attempt to form a useful model of reality. Humans do, just to get through daily life and AI can do the same as well.

As you point out, the concept "sugar-free" does not equate to there being no "sugar" in the dish. Perhaps it means to folks something closer to that fact that no added sugar was explicit in the recipe. The word "sugar" itself has many meanings (the well-known problem of word Polysemy). So there are several similar but distinct concepts at involved here and an entity could have the value of true for one of these and false for another.