Well, my frustration is people who have their assholes so tight as to hate on people who don't use correct grammar. What makes you think you're so much better than they are?
Fucking elitists piss me the fuck off. If you aren't correcting someone else for their mistakes, you're thinking you're better than someone else.
I would consider myself a grammar Nazi and spend an inane amount of time correcting others in their online conversations if not for a few issues.
One, my keyboard is old as fuck. Half the time when I'm typing fast several keys don't register as being hit, and I find myself constantly going back and correcting what I type because of it. I'm sure I'm not the only person in the world who has shitty equipment to type with, so when I see others make the mistake of missing a letter in a word, I usually let it slide.
Two, language barriers. It's a vast internet out there, and half the people on it are fortunate enough to know any English at all to communicate with me on the same level. I won't say any names, but I'm pretty sure English isn't the first language for at least one of the compendium regulars, and any urge to correct their grammar on this board is stifled because I tell myself that very fact.
Three, people make mistakes. I go back and fix grammar errors in my posts about 50% of the time. I can't stand seeing errors in what I type, so I fix it, but I'm not immune to making them. Some people don't bother to go back and check over their posts, after all, it's not like this is an essay being graded or anything. So while I appreciate people avoiding errors, I understand that making them happens to everyone, and I can't expect everyone to be going over their work with a fine comb.