The vast majority of $100 bills are abroad, not in the United States. So yes, of course there's a use here but nowhere near as much as there's a use for $100 bills abroad.
Michael HudsonWhen you say "bank," a bank is a building, a set of computers and chairs and things. The bankers are the people running these banks. They're the chief officers, and they push the loans because they don't care if they go bad. For one thing, they may package these bad loans and sell them off to gullible institutional investors.
Michael HudsonNow, suppose that a homeowner puts down only 3% of their own money or 3.5% for the FHA. That means if prices go down by only 3%, the house will be in negative equity and it would pay the homeowner just to walk away and say, "The house now is worth less than the mortgage I owe. I think I'm just going to move out and buy a cheaper house." So it's very risky when you have only a 3% or 3.5% equity for the loan. The bank really isn't left with much cushion as collateral.
Michael HudsonThere are two definitions of deflation. Most people think of it simply as prices going down. But debt deflation is what happens when people have to spend more and more of their income to carry the debts that they've run up - to pay their mortgage debt, to pay the credit card debt, to pay student loans.
Michael Hudson