Extrovert: Hey introverted guy, you should go out and meet more people. You know you can be more outgoing, right?
Introvert: Sure, and you can stop going to parties, pick 5 or so core friends you spend the majority of your time with, and otherwise spend most of the time wrapped up in your own thoughts.
Extrovert: Why would I want to do that? Wanna go out drinking tonight?
I do think some confusion comes from many extroverts who were SHY, overcame that shyness, and now project introverts as doing the same thing.