You have to get the specific olive oil and wine with the DOC and DOCG stamps, there is a very strict process of approval to get those seals. Without those and you could potentially get something of lesser quality.
That works only if the providers of the approvals are honest.
Read about the adulteration of Italian olive oils like berio and colavita. In the past oh about 10 years.
Italian wines had a history of adulteraton with chemicals. In the past 20 years.