Some people have it quite mildly, so it'd be a bit dickish to quit a job just because you didn't like getting mis-spelled emails even though you could understand the gist of them. But if they're totally incomprehensible then that's a different thing. The fact it was in a library is pretty funny, though.
I read a fairly funny novel years ago called Incompetence, which is set in a near future in which it's illegal to sack or refuse to hire someone for any job for any reason, no matter how unsuitable they are for it. So one of the characters is a coroner who's also a tittering pervert who amuses himself by surgically swapping the body parts of corpses, there's a lapdancer who's male and 100 years old, etc.