Franz Kafka, Party Animal
newyorker.com
newyorker.com
Sartre cites a café waiter, whose movements and conversation are a little too "waiter-esque". His voice oozes with an eagerness to please; he carries food rigidly and ostentatiously; "his movement is quick and forward, a little too precise, a little too rapid". His exaggerated behaviour illustrates that he is play-acting as a waiter, as an object in the world: an automaton whose essence is to be a waiter. But that he is obviously acting believes that he is aware that he is not (merely) a waiter, but is rather consciously deceiving himself.
Sartre suggests that by acting in bad faith the waiter and the woman are denying their own freedom, by using their freedom to do so. They manifestly know they are free, but are actively choosing not to acknowledge it. Bad faith is paradoxical in this regard: when acting in bad faith, a person is actively denying their own freedom, while relying on it to perform the denial.
There's some good commentary after the comic:
"So it isn't that the waiter is being polite when he secretly wants to be a dickhead, it's that he is using the fact that he "is" a waiter to explain his actions, rather than admitting that the actions came solely from his own freedom. "