What's With "cow-orker"?

Why do I see this misspelled so often that I gotta believe it is on pupose? Am I missing something?

It’s intentional. It’s an old Usenet joke, popularized by Scott Adams in Dilbert.

It’s on purpose. Probably started with a typo of co-worker, putting the hyphen in the wrong place. As for what “orking” a cow means, that’s up to your imagination…which is what makes it funny.