It's about the man/woman, not parents. My roommate in college got married a year out of college and took his wife's last name as his Married name. His parents were ok with it. The issue is "culture" vs. "options". I think you stated you were humiliated by that. In my personal view, my mom used to get humiliated and embarassed by many things. I feel most were due to her cultural conditioning and her "feelings" developed through her younger years. Cultural embarassment is a reactionary conditioning sometimes caused by fear of unknowns.

Names are simply labels. Sure, the demarcate the family tree. But in the big picture, they mean very little. A person's true label is his "character known in the community" and not his hame.

Not sure if all this made sense. But my feeling is he/she did it as a way of showing each other that both were important to each other - a form of melding families vs. the cultural tradition of "the man's surname is the law". Each culture is different and one thing I find interesting is evolution exists in our culture - here in America, we enjoy freedoms which may be a little upsetting at times but an open mind feels a whole lot better in maintaining a stress-free life rather than living by the training our parents and culture have tried to "condition" us to believe is the "right way to be."

The only right way is Love.