BCC is completely acceptable in business/professional work. Do you use BCC? If so, for what reasons? Does it really matter if you use BCC or not, as for email you can just simply forward the email on, and others don't know anyway. Same for letters and memos, you can make copies on the copier and provide to other people. These items do the same thing as BCC, so I'm not sure of the issue of using it or not.