Slight Motivation: In Mac Lane and Freyd's books (the latter being a reprint of an older book called "Abelian Categories") they note that instead of defining any Objects in a category we may define an "arrows only" approach by considering the identity morphism associated to an object to be the object itself.
Question: Is it computationally or syntactically easier in category theory to consider a category as objects and morphisms instead of as just as morphisms? In short, is there a reason we keep objects around?