Yes, all genitals seem weird to show people. I don't even show them to my parents. I tried not to take them at all, and instead tried to take a few with angles that obscured any private areas. I think my parents have seen a couple of those, but I don't even send them.
Perhaps the comic is from the mindset 40 years ago. I could easily see parents of that era doing this and thinking it was fine.
That's right. They were never your parents. They were just cake.