There was a time in US history, starting somewhere around WW2, where maximum marginal income taxes were crazy high (like 90%) and you had other wage controls in place at various times.

These high income taxes were politically popular, but companies still wanted to compete for workers. So they found all kinds of loopholes for extra benefits they could give employees at a lower tax rate (or at no taxes at all). Sometimes they even lobbied for those loopholes, too.

See https://en.wikipedia.org/wiki/Health_insurance_in_the_United... for a brief overview, and perhaps follow references from there.