This is, of course, owing to the fact that John believes that he deserves a pat on the head and a cookie for doing what television tells him to do: roar angrily at the children when the parent who's supposed to spend all her time with them and leave him to cower in his alcove cannot hack it. Usually, I use the example of his about to want to beat the Hell out of April for whatever unknown but obviously evil thing she did to make Elly scream that she was done with motherhood but I'd like to switch to an earlier example of why Mike and the others would have been better off being raised by Hannibal Lector: the arc in which Mike bums John's ego-gratification toy sports car of reminding his family that they're a bunch of parasites keeping him from the good life. As we know, the well-meaning goof proceeded to get lost because he was an inexperienced driver behind the wheel of an overpowered car driving at night; he did his best to drive straight home but being a dumb kid meant that he got in over his fool head. Faster than you can say "Well, that escalated quickly," he wound up miles from home justifiably terrified out of his mind of how the angry loudmouth who only gets his fat arse out of his chair when he wants to either threaten someone WITH violence or just plain hit them would react. The reason is blood-simple: a pathetic slob who valued a mechanical contrivance that made him feel like the man he can never be more than flesh and blood people who are bad because they get in his way imagined that Mike was starring in some sort of bad Canadian teen farce. Rather than admit that he was dealing with a freaked-out kid who bit off more than he could chew, Dumb-ass still thinks that his joywagon was the centerpiece of Ferris Patterswine's Night Off.
The irritating thing about John is that when you read his letters, it's pretty much Mike's fault that he sees nothing of himself in his son. Given how he was a non-factor who left Mike to model himself on the only parent he spent any substantive time with, he doesn't actually deserve to.