the fact that my mom kept her maiden name was very uncommon for her generation (she was born in '43). I was the only one growing up who had parents of different last names (unless their parents were divorced and remarried).
Of most of the people who don't change name when marrying, I find that most of them name their kids the husband's sure name (in western countries).
Before my brother's family changed their names to be the same, the kids had the mom's name, I think it is more common in Denmark.
But still unusual.
I know some cultures are very different. A former boss of mine was Indian, and gave his last name history: In general, you don't use last names in the part of India he grew up in, so he had never used one when he had his passport and visa made for coming to the US. He picked his fathers first name as his last name. He later learned that his father actually HAD a family name (since some part of India uses them), but he hadn't used it much. So when he had kids (in the US) he used that name for their last name (it was easier to pronounce). His wife kept her last name, which I think was normal. So they had 3 different last names in his family, which led to much fun when travelling.
Edited to add: He did think of changing his, but once you have visa in one name, it is just easier on yourself to not change that name. Just don't.
btw since we had our birth certificates and marriage certificates at hand my husband and I never had any issues with visas or anything having different names. I'm sure he would need to be extra careful with documentation though, if my husband was travelling internationally with our kids alone.