Well they don't set NODE_NETWORK, so they don't claim to be providing network services. But then I guess the Chainalysis nodes could easily just clear that bit flag too. 

 

It's not quite pay-as-you-go, but I just posted a scheme for funding of network resources using crowdfunding contracts here:

That comment doesn't have any kind of provision for access control, but group signatures could be extended in both directions: the server proves it was a part of the group that was funded by the contract, and the client proves it was in group that funded the contract, but it's done in a (relatively) anonymous way. Then any client can use any node it funded, or at least, buy priority access.

But it's rather complicated. I'd hope that nodes can be like email accounts: yes they have a cost but in practice people everyone gets one for free because of random commercial cross-subsidisation, self hosting and other things.