I never really think of the internet as any different from the pub or work or whatever.
I can go to the pub pre game and there will almost certainly be 3 or 4 people who have 'heard something'. Sometimes it will be accurate, other times it won't be. The only real difference is hibs.net or the Facebook pages and so on reach a bigger audience and the anonymity of the internet means people are more likely to call somebody out about it. I bet not one person would be brave enought call a guy in the pub a Hearts fans, roaster, talker of garbage or whatever other insult springs to mind to their face if they didn't know them.