fwiw:
Food Stamp Act of 1977 (P.L. 96-58) required disclosure of SSNs of all household members as a condition of eligibility for participation in the food stamp program.
Privacy Protection Study Commission recommended that:
No steps be taken towards developing standard, universal label for individuals until safeguards and policies regarding permissible uses and disclosures were proven effective; and
Executive Order 9397 be amended so that Federal agencies could no longer use it as legal authority to require disclosure of an individual’s SSN. (No action taken.)
The Carter Administration proposed that the Social Security card be one of the authorized documents by which an employer could be assured that a job applicant could work in this country but also stated that the SSN card should not become a national identity document.