Just for the sake of it, I'll add that we did have a range of names to use when DD1 was born.
DH's birth certificate had his mothers maiden name on it. He used this til he was 8 & MIL re married. After they married he used FIL's name.
When it came time to grow up & get licenses etc, we also had the choice of using his real father's name, even though he didn't know him.
In the end we dicided MIL's maiden name sounded best & it was easier as well. So DH has his mothers surname, & so do our kids. We also chose that name as DH was the last generation to use the name. All his siblings had their father's name.
So we chose that name to keep it alive as well. Now we have a son to keep it going. (Well depending on how the girls go I guess, lol).

I also have a friend who changed her name to her step father's name when her mother re-married & she kept the name even after they divorced. When she went on to become a young single mum, she decided the best name for her DD was her step fathers name. It is a well respected name in the community & she did it to try to get away from the name that her mother & aunts dragged through the mud.
The step father put a reply notice in the paper to let everyone know he was not, infact, the grandfather, after the congrats notice was put in. Which I think was pathetic & low, considering he had been with her mother since she was 1. But some people are just like that. (Sorry, my anger gets away with me sometimes, lol)