If one brings up that part of the birth narrative, I am assuming that whatever else the New Testament says on the matter is fair game.
Jacob....'s (he looks suspiciously like Angelina Jolie! On the other hand, that is my ugly mug on my profile pict) statement above makes sense. The narrative states that not long after the birth, Joseph and Mary were compelled to travel to Egypt and church tradition relates that they spent quite a while there. It is reasonable to suppose that whatever amount of gold they were given came at a pretty good time. Is this mere coincidence or part of a divine plan?
Many Bible scholars support that theory. It makes good sense. It is still speculation, but at least there is some basis in the delivered text to support it. There was no UHaul truck to bring their stuff, they had to leave in a hurry, probably with what they had on them. It would probably been impossible without the gift of gold. There is also significant symbolism in the gifts chosen by the magi, I suspect that the symbolism is the reason it is in the narrative in the first place, what they did with it afterwards is pretty irrelevant, that is likely why it is not specified.