Ceallach, I think that some people maybe do say things like that in real life.
I know that when it comes to telling someone I thought they were rude, I don't modify what I say on the forum all that much from how I'd say it in real life...if someone I knew asked me for my opinion. If I thought they were really conflicted and trying to modify their behavior, I would gently tell them my opinion. If I thought they were looking for justification for poor behavior, I wouldn't be nearly so gentle.
But the point is, the equivalent to this forum in real life is someone coming up to you, describing something they did, and asking directly, "was I rude?" In any other real-life situation, I probably wouldn't express my opinions at all (either because it would be impolite to do so, or just not remotely worth the effort
). But if someone asks me for my opinion, here or in real life, I'm more than happy to share it with them.
Judging from the way most people respond on here, I'd guess that a lot of people approach real life, "was I rude?" questions in a similar way to how they approach them here. Some people are just more direct than others.