The reason for this whole unseemly display is probably the same one that has Lynn depict John as being a really incompetent dentist who really doesn't care about his patients. It all boils down to a jealousy that she won't admit to and is inspired by a feeling of inadequacy she'd tried to avoid owning up to since she was a child. Behind every huffy comment about too-good-to-be-true types and malicious sniping about people who work towards goals is a frightened woman terrified of admitting that she just got lucky. Since she doesn't want to do that, we have to endure Phil looking like he's a member of Possum Lodge.
This is also why we have to endure Elly's seeming lack of any sense of humor and short temper. It seems to me that what motivates the flung coffee cups, angry nagging, need to steam-roll over Mike when he does something to irritate her and angry yowling about how April fools all of us is a woman terrified of being exposed as an incompetent and imbecilic fraud who doesn't deserve the great life she has. We see this in a lot of people whose real life plan was the moral equivalent of winning the lottery.