what always bothered me about that was how the person was thin before. It kind of implies that the Blockland Forum turns you into a bad person, even though the cause of most bad behavior in BLF is from an outer source.
It's not him getting fat that shows he's a horrible person. that is shown even in panel 1 by the fedora, the angry expression, and what he says (the idea that BLF is the only place to eat is a bare-faced lie).
He chose to get fat and permanently stay at BLF and upset others of his own will. He could have gone elsewhere or he could have decided not to stay, or at least not to disrupt the others.
But the point is, he feels entitled to do what he likes forever because he paid $10 several years ago.