Ah, but that's only a one-directional test. Cheap oil is obviously not olive oil, but that doesn't help you choose in the supermarket aisle if the expensive oil is also not olive oil.
(And, in fact, the expensive oil being the fake is rather the whole point: the Italian Mafia wants to sell something cheap as something expensive and capture the margin; there's no point in just selling something cheap as something cheap.)
(And, in fact, the expensive oil being the fake is rather the whole point: the Italian Mafia wants to sell something cheap as something expensive and capture the margin; there's no point in just selling something cheap as something cheap.)