I can understand both arguments for/against automatic folder creation.
I've installed RC on our intranet, after having had SM for a while and GroupOffice before that, and I've been finding out that IMAP is not very standard for a standard, interpretations vary. I use it with clients on Macs, PCs running Oulook Express, RC on the server and I have been using "Becky" for years. Our organization is also bilingual, English/French,Which has an incidence on the names of the folders because not all clients allow for label for the folders and show the real names of the folders instead. I've had to fight with programs that insist on naming folders the way they want, ie. "Trash" instead of "trash", etc. I kind of remember "Becky" (my email client) once asking me if I wanted to have folders created on the server. Asking is nice. My two cents!