Marriage and women changing their last names

Should the day come that I tie the knot, my preference is that my wife takes my last name. It isn’t something for which I would push if she wanted to keep hers, but it is my preference. It would make things clearer in that it would more immediately demonstrate to outsiders that we are married. Of course, that is only a minor benefit, and besides that, I would not change my own last name, so it isn’t like I could not be a hypocrite while demanding she change hers. I imagine most any modern day person would see things much the same way, but apparently 50% of Americans wildly disagree with me:

While no national statistics exist, some recent studies suggest that women keeping their own name is actually becoming less popular. And a recent nationally representative survey found that half of Americans support women being legally required to take their husband’s name upon marriage.

…why?