Any smart girl would do this. Make sure to open it in a bank that would is well run enough to offer paperless statements. Same goes for any of her bills.
Also, I really hope we don't see Balraj find out and then keep her confined in the house or something. I hope she gets a chance to finish her studies. And after that she should be able to get out, find some job and live on her own. Don't tell me he would be able to lock her up and destroy any opportunities for her. It's just not feasible, especially if she's bright enough and smart enough.
I really do not need to see the idea perpetuated that the girls (or guys) are stuck in such regressive, patriarchal houses. This is 2013 where they have options to leave and not be held under the thumb of people like Balraj.