Many US banks issue a privacy statement to their customers (for this question, assume a credit card customer) containing language like what's below, followed by a yes/no "Do we share?" and yes/no "Can you limit this sharing?" in a table. Examples include the Bank of America Consumer Privacy Notice or Chase Privacy Notice.
One of these areas is:
For our affiliates' everyday business purposes – information about your creditworthiness
which is often followed by "Yes [we share]" and "Yes [you can limit this sharing]." Instructions for how to limit the sharing are provided below the table, usually by calling some number or going to a Web page to set preferences.
Does setting this privacy-protecting preference limit the bank from sharing information about your creditworthiness with their affiliates which are credit bureaus?
If not, why not? Why must the bank tell customers they can restrict the bank's sharing of their creditworthiness data, but then send the data to the credit bureaus anyway?
It seems to me that maintaining credit records/files on individuals is the primary everyday business of the credit bureaus, and that the credit bureaus are affiliated with the banks through formal business contracts. Are either of those perceptions wrong?