Alarming reflection

We keep cats primarily as a source of amusement. They chase bits of string around, get themselves into undignified positions and then sit up and lick themselves as if nothing has happened, and settle impudently wherever they're not allowed and look affronted when chased off. They are an endless source of fun.

Yet from the way they act, you'd think they keep us primarily as a source of amusement. You know that look; you're waving a favorite toy in front of them, trying to get them to chase it, and they're just sitting there aloofly, giving you a disdainful look, as if to say, "What on earth is that strange person doing, and what am I supposed to do about it?"

Who, exactly, is keeping whom?