"Eat the rich" is a gag about class disparity and cannibalism. But it's only joking about the cannibalism.
Assholes think 'you can joke about anything!' means comedy can never be hateful or hurtful, because they only understand comedy as cruelty you're not allowed to get mad at. If Dave Chappelle keeps shitting on trans people, onstage, well that's gotta be fine, because it's onstage. He's a comedian. And therefore a nihilist. He doesn't mean things when he says words! No matter what he also says offstage.
In reality - you can get away with anything, so long as audiences trust you don't mean it. This is why people get a free pass to demean their own ingroup. We assume folks aren't racist about themselves. But with enough context - even that can break. Human beings are fantastic at discerning meaning. So even hilariously clever phrasing can't stop deeply bigoted stereotypes from piercing the social expectations that make stand-up work, and leave people questioning the bit.