Matter of bizarre principle. I cant have any players from City/Liverpool ever or whoever is playing us that match week in my team because I cant have a scenario where I benefit from someone scoring against us.
I also wont pick United players so I dont jinx them.
It does mean I can take the piss out of one of the Liverpool fans in our league when they celebrated City players scoring against them last season because it got them loads of points until I pointed that their team they support lost in real life with title implications though