You're correct, of course. But your complaint here falls on the eyes of people too ignorant to know how stupid they appear, and how that ignorance degrades their posts.
The ones you cite are homonyms - words that sound alike, but have different spellings and different meanings. And their misuse drives me bat-shit. To, too and two are among the most common, as are their and there, your and you're, etc. In American schools, serious focus on homonyms starts in the second grade, and is repeated, each year, in language arts classes through high school. So those who continue to mis-use them reveal themselves to be hopeless beyond intellectual redemption.
Another teeth-grinder is the rampant misuse of the possessive apostrophe. It's rampant in its misuse. In the worst cases, it serves as a warning that an "s" is coming at the end of the word, and the writer has no idea how to handle it, so throws in an apostrophe because he or she knows where that key is and it seems somehow needed in their crippled view of the language.
For the most part, I read a post until the poster's grammatical errors become egregious beyond the value of whatever it is he or she is trying to say. I then write off the poster as illiterate, ignorant, and below the horizon of my attention. Occasionally I'll make a snide remark, but that's more to assuage my offended sense of proper grammar than to harbor any hope of educating the knuckle-dragging poster.
Oh. And, by the way, I too, dislike the use of all caps. I have weak eyes, and sometimes allow typographical errors to creep in to my posts. But all-caps writing to me is a cantankerous old man shouting at me. And I dislike being shouted at.
