I guess Chad Kroeger didn't get the memo that imitation is the greatest form of flattery.  Pictured here is Sum 41's Deryck Whimbely dressed as his ex Wife.  Yes you read that right HIS EX WIFE!  How weird is that?

Kroeger fires back with a great slam.  "Hey Deryck loved the costumes.  We were going to dress up as you guys this year but all the parties have celebrity themes, haha"  BURNNNNNNNNNNN!!