As I've said before, the cover image to Pushing Forty tells us everything we need to know about John. This is because we have to watch the ugly fool selfishly inconvenience his family so he can do something juvenile, undignified and silly and love every minute of it. It doesn't take a genius to realize that were John to be denied, the selfish idiot child would turn into a foul-tempered old man in a nanosecond. All it takes is watching his reaction to his being inconvenienced in the least degree. Elly's fears that Mike is turning into a bloodthirsty, gun-loving, death-worshiping nihilistic ghoul are so much junk to the idiot but his getting a little bit of his dignity taken away is obviously an affirmative defense for the indictable offense of assault and battery because, as I've said, John is what hospital staff call a particularly antagonistic patient: an SHPOS (short for sub-human piece of shit.) Other people are too young or too old to be sensitive about their looks because he cannot and will not feel their pain but his own pain is something he wields like a bludgeon.
This, as I've said before, is owing to John and Eva representing that part of Lynn's psyche that resents being told to think about other people. Not only does she assume that she's being told to never think of herself, the question baffles and angers her because of the child-like inability to understand that people don't see the world the way she does. This means that not only does John think that April was a jerk to not fall in line when they let Mike actually freeload, he's completely in the dark as to why. He might say that he finally understands that April has needs that differ from his own but he can't really make himself believe it.