I send unauthenticated email on port 25, every semester, in front of my students, as part of a discussion on internet application protocols. I can't use "God", because the addresses are validated, but I do send "from" the school's IT director. I even give them the commands to do it themselves (along with a strict talking to about how it's not truly anonymous because their network access is authenticated).
I've been able to do it at every university I've studied or worked at.
I've been able to do it at every university I've studied or worked at.