Well in Japan peanut butter only recently (3years ago?) became available IN supermarkets. Prior to this you had to buy very overpriced peanut butter at import shops. For me a foreigner who has been living in Japan for over 5 years now I think it's surprising he used this as ingredient.
For most Japanese, they are used to eating "peanut cream". I feel thus invention of "cream substance" and "peanut flavor" is a terrible thing for ones pallet. But anyways this is about peanut butter in cooking on Japanese tv.
After when the 'talento' got their dish to try, they were all quite surprised how good food could taste with peanut butter in it. But I can never see Japanese taking peanut butter and jelly sandwiches to work as an alternative to a bento anytime soon.