Some children like to make castles out of their rice pudding, or faces with raisins for eyes. It is forbidden -- so sternly that, when they grow up, they take a horrid revenge by dying meringues pale blue or baking birthday cakes in the form of horseshoes or lyres or whatnot.
Lakers were able to maintain a certain level of talent and success and so were the Celtics. So after awhile it became part of people's sports lore. . .