Calling money a social construct as if that dismisses it as having any intrinsic value is over simplifying to the point of losing all meaning. Of course a $20 bill would be worth nothing more than a similar size piece of rag paper of and when the apocalypse arrives. But that's not because money is meaningless. It's because its meaning is tied to the whole economic ecosystem. As things stand, money gives you options and freedom because you can exchange it for goods and services. If you never see it coming in and going out, that doesn't mean it doesn't exist. It just means you're not looking (which not having to is convenient, right?).