In fairness, I live just off Horsell Common and have done since 1999. You simply never used to see fly tipping there. In the last five years the local tip has become more and more regimented, with charges now about to introduced for rubble and the like. In the same time you see much more crap discarded on the common. Saw an entire discarded bathroom suite and a sofa not so long back. It's anecdotal I admit but I reckon there's something in it.
Perhaps the locals think the Martians will take it away? (In fact, could it be the Martians doing the fly tipping?)