In "The Walrus and the Carpenter," why do the Walrus and the Carpenter cry?

They are crying because they need the sand to be moved for them

The Walrus and the Carpenter Were walking close at hand: They wept like anything to see Such quantities of sand: "If this were only cleared away," They said, "it would be grand!"

they are crying because they want the sand to be cleared away and because there is too much sand