HT2003 - The Compulsories

Certain subjects or themes seem to pop up with extraordinary frequency. Why do so many photographers make images of the predictable? Sand dunes, lone tree on a hill, lacy waterfall, colorful fall leaves blanketing the hillside, barren trees in the fog, beautiful blossom isolated on a black background - - the list itself is predictable. Are these subjects magically attractive, or photographically easy?