Especially when it is so onerous that you realize you are looking bad, such as not taking part in a charity drive or other helpful community activity. Or not observing holidays to such a degree that you respond to "Merry Christmas" by either offering a flat "thank you" or pretending you did not hear them. I think there is a part of us that feels left out socially, and that hurts because we are social creatures
You've just perfectly described my experience as a witness. The charity thing always irked me so much.