But unless you have some evidence I am simply unwilling to believe that banking regulators can make up any restrictions they like without regard for the actual requirements of federal law.
The actual requirements of federal law are often (intentionally) formulated on such a high level that in practice, the banking regulator does end up specifying the actual rules.
Say, for example, a federal law requires that banks "take reasonable measures to impede money laundering".
Now what those "reasonable measures" are is usually determined by the overseeing regulator (eg: the SEC). Sure, you can disagree with their assessment, but they'll fine you anyway and then, the best-case scenario is that after X years in court, the fine gets overturned.
The actual requirements of federal law are often (intentionally) formulated on such a high level that in practice, the banking regulator does end up specifying the actual rules.
Say, for example, a federal law requires that banks "take reasonable measures to impede money laundering".
Now what those "reasonable measures" are is usually determined by the overseeing regulator (eg: the SEC). Sure, you can disagree with their assessment, but they'll fine you anyway and then, the best-case scenario is that after X years in court, the fine gets overturned.