The problem with flaming certain posters is that it is very often exactly this kind of confrontation that they are seeking.

I think a difference should be made between those who would seek to use this forum to spread false information about the school they work for and those who are just trolling for the sake of trolling. The first kind of people should of course be held to rights but the second kind are better off ignored. Perhaps it's not always easy to identify what someones motives for posting are but i take the view that as soon as the conversation starts to head towards the personal stuff then it's not something i'm really interested in being involved with. While sometimes it's very difficult to resist replying to posters who have made personal comments about you, i think it's best to work on the principle that with most posters of this type you're highly unlikely to have the last word. As Gandhi said

An eye for an eye only ends up making the whole world blind

I'd certainly agree that foreigners in China are often prone to disagreement. I'd imagine there are many reasons for this and a lot of it is down to the individuals attitude. However, i also believe that when you consider the normal pattern of life that someone has in their homeland and compare it to when they are living abroad it also contributes to problems. For example, if i were living back in the UK i would have several different and quite distinct social pillars to my life such as my family, my work, my friends (these could also be sub-categorised e.g. family friends, school mates, etc.), my associations through social and sports clubs, etc. etc. To a large extend i can choose who i spend time with and that time is diluted across the different pillars. It's likely that there are some people who i don't like in the certain social circles or at least would not choose to establish a friendship with but because i don't have to see them that much it's not a problem. Compare that to China where with the exception of the very large cities and a couple of particularly popular areas for laowai it's unlikely that you'll be able to maintain those distinct social pillars e.g. the people you work with are often the people you go to the bar with or play football with, etc. Humans are social animals and the potential for conflict is much greater when we don't get to socialize in the ways we would like to with the people we'd like to.

Also as you said people have different reasons for being in China and we might not always agree with each other that these are good or moral reasons to come and live in another country. It was interesting that you used the term "ex-pat" in your post. I wonder how many foreign teachers living in China now would consider themselves to be an "ex-pat"? The term is likely to give the impression that you have been here or wish to be here for a longer time and therefore are more likely to want to contribute to the society and community that you are part of. Compare that to a recent graduate who is basically here on a glorified gap-year and is probably only interested in seeing and experiencing as much of the country as possible in 12months before they head back home. Again these differences give plenty of potential for a clash of ideas both in the real world and on this board.