How does it being a silly answer preclude it from coming from your cultural memory? It can be silly and part of your memory all at the same time. It didn't come out of a vacum. Nothing comes from a vacum. Actually, I didn't think it was silly. Everyone knows that shells and the like were used as native currency and that shells and shiny trinkets from sailors bought native pussy by the score. So I too found your short line funny, give yourself some f*king credit