... and this is why people with severe allergies always always always read the ingredients list, even if the packaging has not changed. And always carry emergency medication.
Isn't doing this illegal? Since it makes people think they're buying the same product they always have but it has actually changed. At least in Brazil, every time the formula of a product, or the quantity in the package, is changed, companies have to disclose that on the packaging.
Here, the packaging must describe the contents and that description must be accurate, so changes must be reflected there. But nothing requires them to say "hey, we changed this" beyond changing the nutritional information, which most people don't pay attention to.