Yes, and not only do we introverts not run up and sing into the microphone, we then feel all inadequate and shamed for not being too stiff and self-conscious to do so. Soooo many games, all through youth group, where I stood on the sidelines feeling miserable because I wasn't joining in the way I was supposed to. And summer camps, where team points depended on the extroverts going out and doing things, and teams who weren't willing to do this were actively shamed by the (very well-meaning!) staff.