I guess Facebook could be a factor, but Single Onion services are useful for all non-anonymous providers who want to service Tor users. Users stay anonymous and

I guess Facebook could be a factor, but Single Onion services are useful for all non-anonymous providers who want to service Tor users. Users stay anonymous and if they got the right .onion URI, they can be sure to communicate with the right service without any certificate authority or so. There has been a talk about this topic at last years CCC: "Tor onion services: more useful than you think" https://media.ccc.de/v/32c3-7322-tor_onion_services_more_useful_than_you_think https://media.ccc.de/v/32c3-7322-tor_onion_services_more_use...