In many cases, merit goods provide services which should apply universally to everyone in a particular situation, an opinion that is similar to that of the concept of primary goods found in work by philosopher John Rawls or discussions about social inclusion. Lester Thurow claims that merit goods (and in-kind transfers) are justified based on "individual-societal preferences": just as we, as a society, permit each adult citizen an equal vote in elections, we should also entitle each person an equal right to life, and hence an equal right to life-saving medical care.
On the supply side, it is sometimes suggested that there will be more endorsement in society for implicit redistribution via the provision of certain kinds of goods and services, rather than explicit redistribution through income.
It is sometimes suggested that society in general may be in a better position to determine what individuals need, since individuals might act irrationally (for example, poor people receiving monetary transfers might use them to buy alcoholic drinks rather than nutritious food).
Sometimes, merit and demerit goods (goods which are considered to affect the consumer negatively, but not society in general) are simply considered as an extension of the idea of externalities. A merit good may be described as a good that has positive externalities associated with it. Thus, an inoculation against a contagious disease may be considered as a merit good, because others who may not catch the disease from the inoculated person also benefit.
However, merit and demerit goods can be defined in a different manner without reference to externalities. Consumers can be considered to under-consume merit goods (and over-consume demerit goods) due to an information failure. This happens because most consumers do not perceive quite how good or bad the good is for them: either they do not have the right information or lack relevant information. With this definition, a merit good is defined as a good that is better for a person than the person who may consume the good realises.
Other possible rationales for treating some commodities as merit (or demerit) goods include public-goods aspects of a commodity, imposing community standards (prostitution, drugs, etc.), immaturity or incapacity, and addiction. A common element of all of these is recommending for or against some goods on a basis other than consumer choice. For the case of education, it can be argued that those lacking education are incapable of making an informed choice about the benefits of education, which would warrant compulsion (Musgrave, 1959, 14). In this case, the implementation of consumer sovereignty is the motivation, rather than rejection of consumer sovereignty.
Public Choice Theory suggests that good government policies are an under-supplied merit good in a democracy.