i have not tried to replicate it but from my conversation on gnusocial:
http://micro.fragdev.com/notice/945147
in context:
http://micro.fragdev.com/conversation/585016#notice-945147
it is a bug. you can only disable it manually but running in desktop it just
connects.
frankly I would not like that anybody with my email address can listen or see
what is going on the house.
it is the equivalent of someone ringing your phone and just opening the line
directly, without ringing or you acepting the call.
it should not do it by default and should not be offered as an easy option to
have.
