I'm playing devil's advocate here (I agree that the whole Tether situation is concerning), but also genuinely curious - is this any different than what banks have been doing for forever with fractional reserve? Even if Bitfinex is overcommitted and there's more USDT in circulation than they have in USD reserves, is there a problem unless a lot of people try to convert at once?
The big difference with Tether is that in traditional banking, fractional reserves are legal, and regulated (i.e. banks are required to prove their reserves, and are required to hold a certain percentage of their deposits).
If there's a run on a consumer bank, and they don't have enough reserves to repay their customers, then FDIC insurance steps in to protect the customers. In this case, there's no protection, so everyone holding tether will be screwed if there's a run.
Issue here is that there is no one giving confidence that Bitfenix has any currency at all, we have to trust their word.
> Tether is sold as a fully-backed instrument, so there's major (potentially billions of dollars of) fraud if it's not fully backed
The fraud issue (not to mention the securities price manipulation issue) is still a big deal.
In a bank with fractional reserves, the assets and the liabilities all add up. If I deposit $100, and the bank lends $80 of that out to someone else, the bank has liability to me of $100 and assets of $20 cash + $80 loan (a loan is an asset on a bank balance sheet). I can't immediately withdraw all $100, but it all exists.
The bitfinex thing is more akin to the Federal Reserve, which actually can just make up money out of thin air. The big difference between bitfinex and the Fed is that the Fed is a federal agency, created through a legislative process and operated with clear public policy goals. Whereas bitfinex is just some random people somewhere claiming they have $billions in the bank.
An unregulated system that allows fractional reserve banking can only end badly. Competition will cause private entities to take increasingly risky positions (if they don't play along, they get crowded out by those who do), and the systemic risk is unchecked. At its extreme, it becomes a ponzi scheme.
No. They are different. The bank turns liquid cash into much less liquid assets (houses, cars, boats, new businesses) by way of loaning out the money. All of the banks liabilities (the depositors) are backed by the banks assets (loans for stuff).