I think one of the issues I'd have if I was a City fan is that the club doesn't get enough credit and recognition from other clubs' fans for what it's achieved. I think a lot of it gets written off as 'they just bought it' whereas the reality is plenty of clubs have spent the same, or more, than City and haven't achieved a fraction of what they have.
Ironically I think one of the fanbases that did respect City's achievements to the extent that the club has been open about using City as a template is Arsenal. I feel the relationship between the clubs has fractured somewhat at a fan level, the last few months in particular although it will never get to the stage where bricks are put through the other team's bus windows.