I had a Vietnam Vet buddy who had nothing to do with banks or the IRS from the time he came home from Nam. Worked for cash, never filed a tax return; they didnt even know he was out here. Until decades later, 2010 or so, when he signed up for - and received his VA Disability benefits, backdated to 1973. He then had a sizable sum plus a monthly payment for COPD, PTSD, and some other injuries. Then he died within 3 years.