Geronimo figured the scum in the park would elect him king of the scum because he’s just as commie and just as hypocritical as he is. I’d bet he still can’t believe they booed him.
Actually, that's my favorite part of the story. It simply didn't register when they booed him the first second or third time. He figures if he keeps giving them another chance, they'll come around in spite of themselves. The man is a fungus. He's right to think he should be treated like the prodigal son by that crowd.