Each of us is a producer and also a consumer. However, we are much more specialized and devote a much larger fraction of our attention to our activity as a producer than as a consumer. We consume literally thousands if not millions of items. The result is that people in the same trade, like barbers or physicians, all have an intense interest in the specific problems of this trade and are willing to devote considerable energy to doing something about them. On the other hand, those of us who use barbers at all, get barbered infrequently and spend only a minor fraction of our income in barber shops. Our interest is casual. Hardly any of us are willing to devote much time going to the legislature in order to testify against the iniquity of restricting the practice of barbering. The same point holds for tariffs. The groups that think they have a special interest in particular tariffs are concentrated groups to whom the issue makes a great deal of difference. The public interest is widely dispersed. In consequence, in the absence of any general arrangements to offset the pressure of special interests, producer groups will invariably have a much stronger influence on legislative action and the powers that be than will the diverse, widely spread consumer interest. Indeed from this point of view, the puzzle is not why we have so many silly licensure laws, but why we don’t have far more. The puzzle is how we ever succeeded in getting the relative freedom from government controls over the productive activities of individuals that we have had and still have in this country, and that other countries have had as well.
The only way that I can see to offset special producer groups is to establish a general presumption against the state undertaking certain kinds of activities. Only if there is a general recognition that governmental activities should be severely limited with respect to a class of cases, can the burden of proof be put strongly enough on those who would depart from this general presumption to give a reasonable hope of limiting the spread of special measures to further special interests. This point is one we have adverted to time and again. It is of a piece with the argument for the Bill of Rights and for a rule to govern monetary policy and fiscal policy.
Milton Friedman – Capitalism & Freedom p.143