The kids are being let out of school early for the annual McVities harvest, an obscure British marine delight that occasionally washes up on the shore, free for the pickings. They are the edible spawn of some of the ten thousand shipping containers that spill overboard in the oceans each year, a small fraction of the 100 million containers on the go around the world. (see the North Carolina Dorito Harvest here)
Other bits of flotsam and jetsam are less delightful. Close to a billion gallons of oil is dumped into the ocean through accidents, cleaning bilges, leaking and runoff.
BBC on McVities
Cookies make a cute story and get international attention, while the day-to day dumping of every conceivable kind of waste into the oceans gets very little notice. Some of it gathers in the trash vortex in the Pacific; see Greenpeace on the gyre here and TreeHugger on Moby Duck. Read also Cigarette Butts: One Huge Problem, Two Solutions.