The optical properties of PdMn0.7Fe0.3, Pd2AuFe and GdCu alloys of different homogeneity have been investigated. Possible reasons for the peculiarities typical of all alloys studied (deviation from the Drude behavior and low-energy absorption of light at ℏω < 0.5 eV) are discussed. Occurrence of these anomalies is related to general features of studied objects microstructure (phase inhomogeneity of medium in the form of presence in high-resistivity matrix of alloys of small inclusions of metal type.