The top marginal rate was 91%, yes, but that rate was for income over $200,000 in 1950 dollars, which is (adjusted for inflation) nearly $2m in today's dollars:

The top marginal rate was 91%, yes, but that rate was for income over $200,000 in 1950 dollars, which is (adjusted for inflation) nearly $2m in today's dollars: http://taxfoundation.org/article/us-federal-individual-income-tax-rates-history-1913-2013-nominal-and-inflation-adjusted-brackets http://taxfoundation.org/article/us-federal-individual-incom... Meanwhile, the median household income in 1950 was under $5,000 (in 1950 dollars): http://web.stanford.edu/class/polisci120a/immigration/Median%20Household%20Income.pdf http://web.stanford.edu/class/polisci120a/immigration/Median... So although there were very high marginal rates at the top, they applied only to people making over 40 times the median income. And just to pay a higher marginal rate than 2015's maximum of 39.6%, one needed to be making around three times the median income in 1950. So you'll need another explanation, because it's unlikely that the risk of being bumped to an ultra-high marginal rate was an issue widespread enough to spur the offer of untaxed health care. And as others have pointed out, it's well-documented that the actual reason was a reaction to wartime wage controls -- given the choice, companies would have simply offered more cash.