The logical aspect of it is that your family back home will be ur tie that will make u to return home, now u decide to go with them it makes them to be doubtful of ur rtd after study. Though there are other ties apart from ur dependants but it is most reliable consideration used by them. Meanwhile, this is not to say that it is not possible. There are some that were so lucky only may be they have other criteria that made it possible for theme to be waived on such issue. I think it is better you request info how ur dependants join u after u get ur permit.