It is well known fact that foreigners landing at Swampy all have suitcases full of plastic trays, beer cans and bottles and other such rubbish, with the sole intention of dumping it all around the beaches and streets of Thailand....it could not possibly be Thais who deliver such containers full to them, who are being irresponsible. The locals do not mind overly, as they then sell them lots of useless crxp to take back home in their baggage!
(USA guys, this is irony again!)