[g42gregory]

Many cryptocurrency websites refuse services country by country, and in the United States case, I saw service restrictions on state by state level. Many financial services (overseas hedge funds) websites refuse access to US persons.

[zamnos]

The Foreign Account Tax Compliance Act (FATCA) requires banks and other financial institutions comply with a bunch of regulation for they pleasure of having an American as a customer. Unless it's a particularly interesting market for a foreign bank, they, as you've seen, just won't do business with an Americans.