I’m thankful for the three ounce Ziploc bag, so that I have somewhere to put my savings.

The joke hinges on the TSA’s “3-1-1” liquids rule, which made the three-ounce container (and the small clear zip-top bag) a familiar symbol of modern air travel. Poundstone flips that mundane security requirement into a self-deprecating comment about personal finances: her “savings” are so meager they fit in the tiny bag meant for toiletries. The line satirizes how bureaucratic constraints can become everyday cultural reference points, while also poking fun at economic anxiety and the precariousness of middle-class life. Its humor comes from incongruity (money stored like shampoo) and from the candid, conversational persona typical of stand-up comedy.