Some people simply don't understand that C is actually everywhere around them. They don't understand that either the language they use is built in C, or the language THAT was built on was built in / on C, etc etc. Simply the importance of the language in history may just be a powerful point on its own. If someone knows quite a few languages and doesn't yet know C, I kind of don't understand why - they do not yet understand the importance of lower level operations, like the functioning of a garbage collector or why their pre-mature optimizations shouldn't even be attempted.
Great article, over all - I really liked it.