Tether and their 45 billion of fully-backed assets (!) are based in the British Virgin Islands, and do their banking through a shady bank in the Bahamas.
Can you point to their claim of FDIC coverage. Brokerages usually have SIPC for securities, I figured coinbase just had privste insurance and wasnt using FDIC or SIPC.
Looks like there is some details here https://www.coinbase.com/legal/insurance
From your link: "To the extent U.S. customer funds are held as cash, they are maintained in pooled custodial accounts at one or more banks insured by the FDIC. Our custodial accounts have been established in a manner to make available pass-through FDIC insurance"
So, should you have the desire to keep cash at Coinbase for some reason, it will actually be held at a real bank and FDIC insured.
The fees, as you explain it, do indeed seem like highway robbery. But there's something very specific about Coinbase in the US: all customers funds from american fiscal residents in USD are FDIC insured (so up to 250 K are safe). AFAICT they're the only one to actually offer this? It's also a real company, with a real address, whose owners are real people, etc.
It's not exactly the "we're convicted criminals operating from the Cayman using some shady bank" type of crypto exchange.