Share 'A cycle mystery'

I'll confess I don't ride a bike but my son runs Big Fun bikes in Haggerston - my wife and I were talking about Bike Hangers, those metal cages that people an safely leave their bikes in, and so I took a look on line at Haringey's provision local to us. There seem to be a lot and most are priced at £36 per annum which seems reasonable BUT... why is the bike hanger by Chettle Court, a block of wha…