Furthermore:
Pursuant to the USA Patriot Act of 2001, the Secretary of the Treasury was required to finalize regulations before October 26, 2002 making KYC mandatory for all US banks. The related processes are required to confirm to a customer identification program (CIP)
https://www.ffiec.gov/bsa_aml_infobase/documents/BSA_AML_FAQ.pdfThe CIP rule provides that a customer generally is a person that opens a new account. 31
C.F.R. § 103.121(a)(3)(i)(A).
Cryptsy put limits on non-FIAT for current and new customers because
THEY wanted to. Nothing more.