OK seriously...
It's not myth, but superstition.
I believe that the first person across the threshold of a house immediately after midnight, should be the man of the house holding money and bread. That will bring money and food to that house all year.
My superstitious dad does this every year. The one year he missed, the steel mills (where he worked) shut down and he lost the THREE houses that he owned in Ohio.
He never missed another year and has been doing very well ever since.