I don't understand why Francisco pretends to be a playboy as opposed to another character, like a bartender. What's the significance of the...

An interesting theme in this novel is the idea of personal
integrity and the importance of being true to one's self. For some of these characters,
integrity is an all or nothing proposition. If they cannot maintain this integrity in
every aspect of their lives, they tend to want to disown this idea and inflict some form
of suffering or pain as punishment for failure. This is especially true in terms of how
characters manage their intimate relationships. But ultimately many of these characters
also have an epiphany or revelation that allows them to reclaim their integrity and
accept their choices and behaviors as necessary to their own growth. For Francisco, his
decision to live life as a decadent playboy is in direct opposition to what he really
wants, which is to be Dagny Taggart's lover. Since he and Dagny cannot be together, he
no longer feels worthy of her, and so the opposite extreme of devoted lover is
promiscuous playboy. For Francisco, this is the ultimate form of self-punishment and
degradation, which he feels he deserves for losing Dagny.