From a classic 2001 article by Milton Friedman, "How to Cure Health Care":
"Two simple observations explain both the high level of spending on medical care and the dissatisfaction with that spending. The first is that most payments to physicians or hospitals or other caregivers for medical care are made not by the patient but by a third party—an insurance company or employer or governmental body. The second is that nobody spends somebody else’s money as wisely or as frugally as he spends his own.
No third party is involved when we shop at a supermarket. We pay the supermarket clerk directly: the same for gasoline for our car, clothes for our back, and so on down the line. Why, by contrast, are most medical payments made by third parties? The answer for the United States begins with the fact that medical care expenditures are exempt from the income tax if, and only if, medical care is provided by the employer. If an employee pays directly for medical care, the expenditure comes out of the employee’s after-tax income. If the employer pays for the employee’s medical care, the expenditure is treated as a tax-deductible expense for the employer and is not included as part of the employee’s income subject to income tax. That strong incentive explains why most consumers get their medical care through their employers or their spouses’ or their parents’ employer.
We have become so accustomed to employer-provided medical care that we regard it as part of the natural order. Yet it is thoroughly illogical. Why single out medical care? Food is more essential to life than medical care. Why not exempt the cost of food from taxes if provided by the employer? Why not return to the much-reviled company store when workers were in effect paid in kind rather than in cash?
The revival of the company store for medicine has less to do with logic than pure chance. It is a wonderful example of how one bad government policy leads to another. During World War II, the government financed much wartime spending by printing money while, at the same time, imposing wage and price controls. The resulting repressed inflation produced shortages of many goods and services, including labor. Firms competing to acquire labor at government-controlled wages started to offer medical care as a fringe benefit. That benefit proved particularly attractive to workers and spread rapidly.
Initially, employers did not report the value of the fringe benefit to the IRS as part of their workers’ wages. It took some time before the IRS realized what was going on. When it did, it issued regulations requiring employers to include the value of medical care as part of reported employees’ wages. By this time, workers had become accustomed to the tax exemption of that particular fringe benefit and made a big fuss. Congress responded by legislating that medical care provided by employers should be tax-exempt.
The tax exemption of employer-provided medical care has two different effects, both of which raise health costs. First, it leads employees to rely on their employer, rather than themselves, to make arrangements for medical care. Yet employees are likely to do a better job of monitoring medical care providers—because it is in their own interest—than is the employer or the insurance company or companies designated by the employer. Second, it leads employees to take a larger fraction of their total remuneration in the form of medical care than they would if spending on medical care had the same tax status as other expenditures.
Employer financing of medical care has also caused the term insurance to acquire a rather different meaning in medicine than in most other contexts. We generally rely on insurance to protect us against events that are highly unlikely to occur but that involve large losses if they do occur—major catastrophes, not minor, regularly recurring expenses. We insure our houses against loss from fire, not against the cost of having to cut the lawn. We insure our cars against liability to others or major damage, not against having to pay for gasoline. Yet in medicine, it has become common to rely on insurance to pay for regular medical examinations and often for prescriptions.
If the tax exemption for employer-provided medical care and Medicare and Medicaid had never been enacted, the insurance market for medical care would probably have developed as other insurance markets have. The typical form of medical insurance would have been catastrophic insurance (i.e., insurance with a very high deductible)."