Narcissists and sociopaths can’t handle genuine, heartfelt interaction between themselves and other human beings; they just aren’t capable of communicating on anything other than the most superficial levels.
So, rather than try, they simply alter their perceptions of those around them. They willfully ignore the thoughts, feelings, rights, and beliefs of other people and reduce them to mere objects. In this way, they don’t see a person, but simply an inert physical form.
They do this because they are familiar with objects; they know how to deal with them and use them for their own personal gain or satisfaction. Viewing individuals as objects allows them to treat them in the same way that they would a phone, car, table, or bed, for example.