This may be due to a case (non-)sensitivity issue. I have two subfolders on the mail server called "Spam" and "spam". On the mail server (Dovecot), these are directories ".INBOX.Spam" and ".INBOX.spam".
Suppose we allow (non-porn/violence/political/illegal products) spam, having Staffers move discovered spam to a Spam sub where the Music, PCA, Sports, etc subs are above the Lounge (instead of to the Trashcan). It could be titled, "Spam." ;)
Spam is ads. We have lots of ads here. Some members like to look at ads, and some even like to click on them if a good deal seems to be there.