Really; where to start?
Firstly, let me address the matter of singing; Much of the away-fan singing, as it is when we are the away-fans, is almost choreographed, because we/they are a (relatively) small group gathered together. That gives the singing more impact and is easier to pick up on microphone than several disparate singing groups. I find that, when watching a tense game, mindless singing is a distraction. Most singing and chanting is initiated either by an urge to motivate the team or as a response to actions on the pitch. When the game is being played out in the careful, patient-approach way that we play most of the time then singing seems an irrelevance. The 'oohs' and 'ahhs' and shouts of encouragement when we attack at speed are loud and clear. You can only sing for 90 minutes, regardless of the state of the game, when you are totally canned up, and what else do travelling fans have to do?
Empty seats: The core of City fans are Manchester people who attend every game they can; season ticket holders attending the home league games and subscribing for the cup schemes. On top of this, with our success as a team, we are still in every competition going and games are coming thick and fast. Believe me, the time will come when, just like the plastics at the swamp, we will be a larger global entity and be inundated with wealthy-enough tourists paying homage to the brand 'City'. After all, a great proportion of the swamp-attendees are first-timers and once-in-a-lifetimers. If we remain a club supported significantly by a loyal, life-long, local fan-base, then we must accept that we will struggle to fill the stadium for the umpteenth home game in a fortnight, on a Tuesday evening. Some of you would also complain if the stadium was topped-up with tourists watching the action through the rear view of their I-phones.
Leaving early: If people want to leave early then what the hell? Personally I would never leave early, and that's not because I have an easy journey home. I would never leave early because I would have missed some of the most breath-taking and exhilarating moments in our season, or even our history. (I got home at 1.15 this morning, by the way, and I know others who had at least a further hour to add to their journeys).
A previous poster nailed it; Why are we concerned by what others might write or vocalise? We know how much we love City, that the fans in the stadium are 'proper fans' not supplemented by voyeuristic tourists, that we always sell our away ticket allocation, and that we have the best, most loyal fans in the league. Be strong Blues!