One interesting use of credit cards which you may find funny is when Ethereum was first launching it's ICO I remember hearing rumors about some of the founders maxing out their credit cards. Would it be shocking if some of them did that to buy mining rigs or to buy into the ICO itself? If they used credit to get assets like Ethers then who could blame them looking back?

Most people use credit to buy junk they don't need, or to buy a house, or to buy a car, none of these are assets and most don't appreciate in value. Houses get taxed, cost money to maintain, along with cars.