Done.
When you want to hire a Boris bike you use a card (could be a fob, could be a key) to unlock it from a pre-installed safe place. With a Marmoset Stand, you use a card (could be a fob, could be a key) to lock it to a pre-installed safe place. You don't need to carry a lock which weighs more than some carbon frames with you all the time. Sure, you pay a small fee but that covers compensation should anything untoward happen to the bike as well. Besides you already pay a small fortune for a D-lock. Even when the bike's gone. You will no longer need a D-lock or a chain. The point is we already have a locking system in large parts of London. It's just that we think of it as an unlocking system.
Note: if you like to wear a chain around your waist as you cycle there's nothing to stop you continuing to do so. In fact, it can now be much lighter because it will only be there for the look not the lock. And possibly holding up your trousers, of course.