I'm a dark haired, dark eyed, dark skinned Southern Italian (-American). Sure, we a have few blue-eyed redheads in the family, seems there is a deep strain of such hued folks in Sicily, but we are mainly, and most definitely, stereotypically Mediterranean in appearance
When we lived in the Bronx it was pretty much a mixed bag of nationalities, accents and colors. Where we lived in Queens, not so much. Not that Queens wasn't multi-ethnic, it was, just not my neighborhood, so much.
And then there was television, magazines, advertising - pretty much all Anglo, and blond haired/blue eyed. I grew up thinking Anglo's were exotic. Because they didn't look like me or my family.
When I started dating I gravitated to the All-American Anglo looking guys. They were different! They were what was desirable in this country (or so it seemed.) Just as my dark good looks were considered exotic and desirable to a lot of the Anglos.
Once I did go out with an Italian guy, and while we had a good time we decided that a romance wasn't in the cards because, as he said, "I really like you but you look too much like my sister!"
I'm sure I laughed at that because I distinctly remember saying to an Italian-American fellow "I can't go out with you, you look just like my Uncle Al."
I wonder if that happens much within other nationalities/ethnic groups? It must, surely. If you stick with your own kind, it stands to reason that someone is going to look like someone else. And that someone else just happens to be a family member
And let's face it, the thought of rolling over in bed in the morning and coming face to face with your Uncle...Eh - I don't think so.