>But if I give them 1USD and get back 1USDC, which later can be exchanged back to 1 USD, where are they making money?
Historically that's basically how banks have made money. Issuing bank notes while earning interest on the capital they hold. Typically they juice the rate via fractional reserve lending, ie they lend out more money than they have. However if they aren't able to do that, they still get to keep the interest from the deposits (say by buying Treasuries).
My guess is that the stable coins will continue to be more and more common, but then cryptocurrencies will rediscover fractional reserve lending, and new ideas like pegging a coin to the S & P. The pegger will charge a small service fee, the holders will be able to rapidly move money they spend, almost instantly between S&P (or other basket) pegged coins and stable coins.
There will be enough competition over being the holder of stable coins and enough competition in that system they I would expect them to offer rebates on transactions, and not have to charge merchant fees. And since they will be centrally cleared and not have to deal with mining and so on, the transactions ought to clear instantaneously.
Historically that's basically how banks have made money. Issuing bank notes while earning interest on the capital they hold. Typically they juice the rate via fractional reserve lending, ie they lend out more money than they have. However if they aren't able to do that, they still get to keep the interest from the deposits (say by buying Treasuries).
My guess is that the stable coins will continue to be more and more common, but then cryptocurrencies will rediscover fractional reserve lending, and new ideas like pegging a coin to the S & P. The pegger will charge a small service fee, the holders will be able to rapidly move money they spend, almost instantly between S&P (or other basket) pegged coins and stable coins.
There will be enough competition over being the holder of stable coins and enough competition in that system they I would expect them to offer rebates on transactions, and not have to charge merchant fees. And since they will be centrally cleared and not have to deal with mining and so on, the transactions ought to clear instantaneously.