George Seton: What happens to all those tents left at festivals?

We've seen the photos and videos on social media going viral every year, showing the mountains of rubbish that have to be dealt with after every new year's festival. Tents that got hit by the weather, covered in mud, with festival-goers who just don't want to deal with packing it back in their cars.  But the clean up still has to be done, so what happens to all the rubbish left behind?  LISTEN ABOVESee omnystudio.com/listener for privacy information.