Right spelling; wrong word

I try not to make fun of the linguistic foibles of my fellow beings. The reason is that most of what people call "mistakes" are simply other dialects or emerging changes in the language. A case in point: If you go to a supermarket, you'll see a sign that says something like "Express line. Ten items or less." To be strictly in line with traditional usage, it should be "Ten items or fewer." But the distinction is disappearing, so I tend not to fuss about it.
However, there are times when I simply can't resist. So, here are my offerings poking fun at people who mis-use the language. The first is from a sign on the gate of a swimming pool at a university where I taught. The sign read, "This pool for faculty and staph only." I don't recall that I ever used the pool. The second item is from a sign in my favorite hot springs, where I to to (frequently) soak. The sign notes, in part, that people with sores, cuts, open wounds, or other legions can't use the pool. I'm surely glad, because I wouldn't want to share the pool with a legion, especially if it's the French Foreign one.
Laughs aside, there's a reason for these glitches. Though this is hotly debated, I believe that there is a sharp disconnect between our oral language processing and our written language processing. The systems don't talk to each other all that well, and information from one doesn't naturally seep over to the other. So, a person who's a good talker and an intelligent person may not be a good speller. Or may well exhibit the hallmark of modern computer-assisted writing: all the words spelled correctly, but not necessarily the right word.