'Lock 'em up'

Is this sort of thing blighting your neighbourhood? There were three of these placards along my commute chained to either lampposts or in this case a tree. Most seem to have been destroyed. We must be a nation of horders to need all these lock-ups. You'll notice it is lying down in the picture. When the council chaps come to cut the grass they move it out of the way but don't remove it. Not their job, see.