Richard Parker lives in a small Philippine fishing village. He has extensively studied contemporary seashore foraging, fishing, and bead-making, and has thought and written quite a bit about prehistoric versions of same. Parker riffs on my theory of the origins of money, adding many interesting observations he's made about shells and bead-making along the way. He has some good comments about the debate over whether the older finds were actually beads or the puncture holes were just a result of the way they ate snails. Although he questions the rush of archaeologists to conclude that they were beads rather than worked prey, he concludes that Nassarius, at least, was too small for eating. Piercing them and sucking out the contents would presumably have been more trouble than it was worth.
Archaeologists recently discovered similar punctured Nassarius shells in Algeria and Israel that date back to 90,000 to 100,000 or more B.P.