I agree to a point. A public place like this, you're right. EX: I fly for company X so there's not much chance of running into Joe Shmoe, who made fun of my mother, because he flies for company Y. But in smaller forums, especially company specific, people tone it down because they know that on any day, they could run into the other person.
There was a noticeable difference when the XJT crackpipe changed from screen name to real name.