In our society, some women grow up expecting that one day they'll have to give up their last names when/if they marry (a man). The part of a person's identity that is tied up in their last name, which is often inherited from their father, is more fixed for men than it is for women. There is a degree of uncertainty that comes with knowing that you will one day have another name and not be entirely the same person. Old friends won't be able to look you up as easily. Part of your identity is defined by your husband's, not to mention the inconvenience of changing your bank cards and social security/ID cards. Since I am particularly fond of my last name, this has never been an appealing concept to me.
Names seem arbitrary and a very silly thing to argue over, but they signify a lot in our society. There is a certain degree of entitlement that men have when it comes to their names. They aren't expected to change anything about themselves when they marry. Granted, if a woman genuinely wants to take her partner's name, she should be free to do so, but that should be a choice, not an expectation.
I recently talked to a straight, male friend of mine, who had a lot to say about this debate. He mentioned how he always grew up imagining that one day he would share his name with someone, and she would be "Mrs. [insert his last name]." It was something he's always wanted to have in the future. I asked him if he would ever consider taking his wife's last name. He said no, that it would be too weird, and he'd feel cheated out of something he always anticipated he'd keep: his name, a part of his identity.
I think that in itself is a privilege. It's a privilege to expect that one day someone will take your last name so that you don't have to give it up. You will share your identity with someone else's identity, and they will sacrifice theirs. There is a sense of ownership and possession in the idea of naming someone else as yours. Some find it endearing, which is their opinion, and others find it slightly oppressive.
Throughout history, the legacy of last names has carried a lot of weight. Names have the power to both control and protect a person. Slaves in North America have historically been labeled with the surnames of their owners and were thus the property of America.
The power dynamic of name-giving is something that we don't really think about on a daily basis. It seems like a small detail when you are marrying someone you love. Yet, is it only small because it's been constantly reinforced in our society even though it is a tradition that legitimizes the identity of men more than women?
For a lot of us, our family names come from our paternal side, and there's nothing we can do to change that unless we change our names to something that we create. The fact that women do not feel that they can keep their birth names and marry without causing a rift in their family lives and causing name complications for their children is pretty frustrating. Not to mention the terminology of their birth name; it is their "maiden" name. "Maiden" implies that this is the name only a virgin can have, since her marriage and future sexual partner (husband) is chosen by her father, and her husband will in turn own her sexuality, since he deprives her of her "maiden" name.
Maybe that seems like it's taking it too far, but I think this is an issue worth discussing further.