A common Mennonite last name is Dyck. Unfortunately, some people have over the years altered their spelling to Dick. And even more unfortunately, the family of one of my colleagues named two of the boys Bernard (Bernie) and Harold (Harry). They actually went by these short form names. As time went on the first changed both his first and last name.
I know of two women whose first name just happened to be part of their married last name as well. eg Hazel Hazelmire. A very unimaginative family I know named their son Peter Peters. Another one of my friends married a man whose last name rhymed with her first name. After her first date with him, she said, "He's a really nice person, but I can't see the relationship going anywhere because I just can't see being known as Sheri Cherry for my whole life."
Around where I live there are a number of native people with traditional last names such as Nicotine, Yellow Blanket, Greyeyes, etc. At my mum's school was a family where the mother's last name was Big Ears. The children were named Charles, Batman, Robin (male), Wolfsong (Bubba), Fluttering Sparrow, Shania and Brandi. I'm not sure if they chose to go by their mum's name, or if they looked for a different surname.