Besides it being a bit of a weird question, I do think there is some kind of sense in some cultures that fathers want to have boys.
Well, in our culture, the girl gets married and goes to her in-law's house, which becomes her house from then. The boy remains at the father's home , takes care of responsibilities, and ultimately, it becomes his home. This is the reason, people want a boy, but they also want a girl - having each is the best combination. Thankfully, God has gifted us both and we are truly enjoying their company, their difference and what not..
Have you noticed at changes over time in the culture? Do you think it will ever balance out and won't be tied to finances?
It has changed to some extent, people who do not have a son and only girl child no longer feel the same as it used to be decades back, because girls are now much more capable of being financially independent and manage the finance. But then it's not only about finance, the culture of girl going to her husband's house and settle there makes the difference.
The concept of boy child taking care of Parents will change most likely in couple of generation, we being the first.