Because it was thrown on the ground by some jerk?
the mess left behind was incredible, caine. bombs and bins don't really mix well in London, so even at events like these, places to dump waste are far and few. the clean-up crews are excellent and putting everything back to normal...
Going by this shot, I'd say it had to be close to overwhelming. I'm glad it's getting cleaned up, but that is not a job I'd want to do.