I personally think that correcting the spelling error was the proper thing to do. Clearly the OP did not know how to spell Columbia and he spelled it wrong three times. Such a mistake would be a kiss of death if replicated on an application.
I agree that spelling is important. Unfortunately the guy trying to be a smart-ass left himself wide open to attacks because of his ignorance of geography and his misuse of a comma. His snideness coupled with his mistakes makes him look like a jerk unqualified to criticize people. Maybe he will check his own writing before trying to get a laugh pointing out the errors in others'.
You have at least 1 missing comma as well. The point was not to be snide, it was to point out a CRITICAL error...anyone can make a spelling or a grammatical error, but because the OP made the same mistake more than once, it appeared as if they didn't know the difference.
Please get over yourself!