Actually, from what John Morrissett said in a past posting on the subject, if a USGA event like the U.S. Open was to take place at, oh, say The Ocean Course, the USGA would designate many of the greenside areas as bunkers but further out would be transition areas where clubs could be grounded. (We like to call them "transition areas" vs. "waste areas." If you read the Harbour Town chapter in Pete Dye's "Bury me in a Pot Bunker," you'd know why...)