Fifteen years ago there was no "Facebook, Twitter, Google+, Match.com or even GrubWithUs"... I was barely able to dial up on the nascent and overpriced Wanadoo at that time.
What is so special about plastic? In thousands of years there will be geological layers filled with the stuff, fundamentally no different than all the rock layers and fossil layers laid down at any other time.
Plastic decomposes in "only" 400-500 years. So while we might have a problem with it now, it's all gone in a fraction of a second, when seen in a geological timeframe.
Join Facebook, Twitter, Google+, Match.com or even GrubWithUs if you/he wants to meet random strangers.
But please don't throw trash in the ocean unless it's biodegradable.
<stepping off my soap box>