I saw a good post about this a while back, that referenced Cory Doctorow's concept of Adversarial Interoperability. Basically, by making their product data -- i.e. the databases of how names map to grid references -- rather than a standard or a service, W3W locks out competitors by copyrighting the core capability. They have a monopoly over the addressing scheme, and interoperability is impossible. I think it gets straight to the heart of the problem.