Its his archetype. He’s a jerk protagonist and the show fully treats him like so. He’s constantly trying to take advantage of people, specially Darwin and has a massively inflated ego. Big part of the comedy is meant to be watching his plans deservedly blow up in his face.
His siblings suck too: Anais once tried to commit piracy at a movie theater and wanted to watch a horror movie at her age because she thinks she’s seen horror but what she saw doesn’t count.