Most grammar errors are either the result of ignorance, or just typing the same way that the poster would speak informally in a casual conversation. In either case, the poster is typing what he intended to say, just as he would say what he intended to say if it were a verbal conversation. Poor grammar is not necessarily a reflection of a lack of knowledge on the subject matter, especially if the subject matter is sportz.
Typos on the other hand are just lazy. If a poster doesn't take enough time to proofread what he wrote, then a reader can assume he didn't take much time to think about the subject matter either. The existence of typos suggests that a post is more emotional than thoughtful!!!1!!1!!