My wife was 18 when we got married. She wasn't "well known". She wasn't a feminist. But she kept her last name and it has never been a problem - except for PayPal.
Our kids have her last name as their middle name and my last name as their last name for convenience - mainly the school's convenience.
Personally I hope some day we go to a system where you turn 18 and pick the name you want. I've known at least two couples where when they got married they didn't choose either name, but took a name for "them". I personally would like to see more of this, but then I'm a bit of a romantic.