Not to detract from the man's project (which I think is cool), but every little piece of garbage in the ocean does add up. Oceanographers have mapped garbage patches in each of the oceans, e.g.:
If this were a fad, you might have a point.
Saying 2000 bottles is not a big deal in the grand scheme of things is shortsighted and irresponsible. Millions of tons of garbage doesn't appear in the ocean for no reason. It exists because everyone thinks to themselves "hey, the ocean is a really big place... what harm does a few bottles really have?" The problem is only getting worse, and after all.. we haven't had plastics for that long.
There's no justification for throwing plastic bottles in the ocean. It doesn't improve the environment in any way, but it currently negatively affects hundreds of species.
He had no meaningful effect.