I actually admire the fact that they take bicycle theft seriously there.
In my East London flat I look out on an otherwise secluded balcony where a certain gentleman stores an ever-changing selection of nice looking bikes. I suppose it's possible that he's a legitimate bicycle trader, but given the fact that it's a) a total crackhead flat, and b) he doesn't seem to treat these nice bikes with any respect, just dumping them in a heap, I'm 99% sure they're stolen. I'd report it if it wasn't totally pointless, because the London Police don't care about bike theft.