One thing which is quite common is for people to attempt to impose their own particular preferred social norms on the internet. I'm sure we'll get a funny dose of this when Sprezzatura Siegel writes his book. It's generally condescending, it assumes a lack of self-awareness on the existing participants in a particular internet subculture, and of course is generally utterly ignorant of how and why things are the way they are.
Shorter me: stop crashing my party and telling me how to act.