1) Collingwood, forming out of the ashes of the red, blue and white team Britannia, were forced to change to white and black because of Footscray.
2) Until recently, Collingwood wore mainly white with black, while Port wore mainly black with white. Much like Geelong/Carlton, there would have been no clash. Only Collingwood reversing their colours made a clash.
3) Port Adelaide has clearly been a more successful team historically, and certainly in the past 50 years, than Collingwood.
4) Port Adelaide Power have put some of the most hideous guernseys ever seen on a football field (except for the infamous Hawthorn diamonds strip). What is wrong with solid colours? Why do they need teal with lots of tiny silver triangles and a photograph of an actual lightning strike? Why not solid fields of colour like everybody else?
5) Incidentally, the prison bars design is decidedly ugly. Historical, but ugly.
6) If Port Adelaide and Collingwood weren't so mutually arrogant with each other, Nick Stevens wouldn't be at Carlton - so thanks, guys.