Some words have more than one meaning. Materialism as a philosophy traditionally refers to the viewpoint that philosophies such as idealism are wrong. In this definition of Materialism, the argument would be made that "mind" as a concept that transcends the physical brain is not valid. Anti-materialism would refer to all philosophies that propose some form of metaphysics.
However, there is another meaning of anti-materialism and that is the attitude of attempting to live life with the fewest possible possessions. This definition is not what is traditionally meant by an anti-materialistic philosophy, but is a common use of the phrase today.