My in-laws are from Monopoli, a town in northern Puglia, Italy. After getting engaged to my future wife, 26 years ago, I got into the habit of bringing them bottles of extra virgin oil from various production areas, some of which were real rarities. However, their opinion about these bitter, pungent oils never changed, and they would always say: Michele, we believe you when you say that they are nice, but we find them bitter, “acid”.
Is it a question of taste? No, of culture!
My father-in-law uses tons of chilli peppers (like most people from Salento), and even adds it to his vegetable broth. Yet he was brought up to believe that olive oil should be sweet.
I still harbour some hope for mother-in-law... She recently confessed that never before, when preparing a meal, had she felt the irresistible urge to pour some olive oil on her plate and mop it up with bread.
We must have faith, and never give up.