Is it a 成语? I'm wondering about its range of meanings.
One source suggests, "use the rhetorical tone to indicate that you have no time or no mood to think about your family problems."
Another says, "usually said during a national crisis." Is that sarcastic, i.e., the crisis threatens to make you homeless?
Would "何以家为?" be appropriate when someone (who doesn't understand a nomadic lifestyle) is a bit pushy about asking for my address?