All crumbs are not food-related. You can give your full attention to someone or crumbs. Are such crumbs of value? How?

You can know about something and just give crumbs...dibs/dabs/infinitely small pieces...to others so that you will be the only one who knows the full story. You can be civil/polite/respectful or the opposite. Are your crumbs (figurative ones) more valuable than other people's crumbs? How so?