I agree with @mercury ranique.2170 and @"Danikat.8537" that the medium is not the issue.Also, while an occasional email from the Guild might be read by a few members, I would expect that most Guilds would mis-/over-use it to spam and annoy their members (e.g. "Guild Mission Today @7pm" "Guild Missions in an hour", "Guild Mission in 10 min", "Guild Mission starting NOW!")And it would annoy me, if those Guild emails would clog up my inbox and would prevent me from seeing/getting "important" emails from the game, trading post or personal emails from other players.