Rihanna had to put some of her die-hard fans and surrounding paparazzi in place recently while shopping at American Apparel n the West Village in NYC.  She was exiting the store when she encountered a mob of people blocking her path, so she had to tell them to "back it the f*ck up" so she could go on her way.  Even though the words may have been harsh, she didn't say it in an aggressive way.