Who started the trend of celebrities posing nude on magazine covers?  Demi Moore!  Yep, she started the naked cover trend in August of 1991 on Vanity Fair’s cover – posing while heavily preggers.  She posed again a year later for the same magazine, and then again on Rolling Stone’s February 1995 cover.  Since then, many celebumoms (including Angelina Jolie post-Shiloh, seen above) have taken it all off – or mostly all off and shown us their famous assets. More covers after the jump! Why do they pose almost naked for magazines? ...