Yes the specific object is dumb, both because it's design has holes, and because there are better ways to get it's ultimate function. But the market for someth

Yes the specific object is dumb, both because it's design has holes, and because there are better ways to get it's ultimate function. But the market for something like that is not limited to the exact specific population of homeless in London. A thing like that could be produced in the volume necessary to get economy of scale, simply by not being limited to one city and a single particular model of bike, or even limited to the homeless for that matter. If you don't understand that, then you are in a poor position from which to call anyone else dumb.