I've never actually been called a "know-it-all" to my knowledge, but many people have thought that about me through the years. Not correcting somebody (especially when it's something related to science or one of my other big special interests) is like a compulsion for me, too. It just gnaws at me inside and irritates me until I can correct the person. Now, I can let a lot of errors go by now than I used to, but I still need to correct for science errors.
I rarely correct people as a way to show I'm superior, though. Most of the time, I just want people to know the correct answer in case they care. But unfortunately, NTs DON'T care, as others have said. They just seem to have no interest in facts/knowledge. The only time I am arrogant and want to prove I'm superior in knowledge is when somebody directly challenges me and says they know more about one of my big special interests than I do. I've had several I Love Lucy challenges, and after I shot the know-nothings down, I walked away feeling victorious. 
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Helinger: Now, what do you see, John?
Nash: Recognition...
Helinger: Well, try seeing accomplishment!
Nash: Is there a difference?