Eh, it's the internet. Does it really matter if people are rude? I understand this site is for discussions related to subject matter that is somewhat frowned upon in the vanilla day to day, but to let some faceless post by a screen name get to you is just silly.
To me, it seems that the majority of the "rudeness" happens as a response to one of a few different circumstances.
• Posting content in the wrong subforum. If it has a place, post it there. If I wanted to read it, I'd go find it.
• Being an idiot. This can apply to knowingly, or not knowingly doing or posting something that is just inexcusable. This is a site for acceptance, yes, but common sense and the rules of society still apply.
• Just general trolling. But in this instance, you have no leg to stand on when arguing that people are rude, since that was the goal.
• Then there is the misinterpretation of a post. This applies to broken sarcastometers and the inability to pick up on the inflection of a post.
• Posting like a horny 17 year old nerd. This applies to both being just creepy, and one handed fap material. We don't believe your story, and no girl wants to see your man meat. Get over it.
And I'll end my lecture with my personal pet peeve.
•Basic spelling, basic punctuation, and basic grammar. I'm not a militant nazi about it, but If you want my acceptance, make sure I can understand you.
I'm not saying the op is guilty of any of this, just giving my observations and opinions as to why it happens.