I suppose if there is no close community in an area, that still remains the case even if you give people the means of broadcasting to one another. If people had wide friendship links amongst the community, then youtube-level trolling would be out of the question, because it makes you look bad amongst your friends and acquaintances, but if you don't know anyone, there is no clear barrier to that kind of behaviour. You're still operating by the rules of an online forum, not a local community.
The other thing is that certain topics will enrage anyone in any forum, no matter the social connections. This includes neighborly chats, TV talk shows, dinner parties, classrooms, offices, pretty much anywhere you have humans talking about issues that are important to them and affect them personally, you'll get all kinds of behavior and language.
Unless you have a dedicated moderator of a debate, one who everyone agrees is the moderator, the floodgates are open and the tone of the discussion can go in any direction. This is especially true when the consequences of the debate can mean a new pool is or isn't built at whatever cost down the road from where we live. "Friendship" among the participants won't stop someone speaking out against such things if they feel strongly about it.
