Maybe I'm not being clear. Happens occasionally.
Food grade designation is meaningless for our purposes here. Just because something is suitable for eating doesn't mean it's suitable for inhalation. All food flavorings sold at supermarkets are food grade, but I wouldn't use all of them for vaping (think oils, diketones, colorings, whatever). Just like we wouldn't use food grade VG or PG as a diluent for our eliquids--only higher, purer pharma grade (USP) is recommended. The same applies to e-cig flavorings.