Its is against FB policy to create fake accounts:
https://www.facebook.com/legal/terms
Registration and Account Security
Facebook users provide their real names and information, and we need your help to keep it that way. Here are some commitments you make to us relating to registering and maintaining the security of your account:
- You will not provide any false personal information on Facebook, or create an account for anyone other than yourself without permission.
- You will not create more than one personal account
- .....
If you find you real identity account disabled and you are banned from Facebook for violating their policies just to use a fake identity to participate in a crappy group that wont be around this time next month its your own fault.
Just sayin...