Aside from the obvious reason that draws all of us to this board, one of the great pleasures I get here is the opportunity to flex my vocabulary. Words and phrases that one simply cannot use in everyday life can be interjected into a written post. At work, I often find myself mired in meetings with a roomful of college graduates and I get the "deer in the headlights" look should I slide too far down the list of word choices. I, also, am asked to write "How to" instructions for the computer operators across the company, on occaision. I was instructed to "dumb it down" after using "ergo" in one such paper recently. Posting here liberates a body.
That being said, I try and remember that everyone's grasp of words and grammar is different. Holier than thou I ain't. I may point out a mistake to someone who has skills and will not be insulted by my telling him. However, if I do not know the writer and his abilities, I will forgive and refrain from saying anything. People didn't join this board to have their wordsmanship critiqued. It's all about the cardboard.