Joking in a culture, in our culture, stands in a symbiotic relationship with glibness, shallowness, and hypocrisy.
Glibness, shallowness and hypocrisy play a role, when a party is unable or unwilling to inhabit a role fully or be emotionally honest or open. So for example a funeral director’s “I’m sorry for your loss” when he actually doesn’t feel sorrow, he feels glad at the chance to make money. We don’t really want the funeral director to talk in a way where truth and falsity are the paramount virtues.
But identifying glibness, hypocrisy and bullshit is almost intrinsically funny, because it involves taking focus away from the pretense onto what is being ignored. For example, the comedian Andy Richter mocked a sentimental bumper sticker published by dog lovers that depicted a paw and the words “Who rescued who?” The sentimental point of the bumper sticker is that just as the dog owner rescued the dog from the pound the dog rescued the dog owner from a life of loneliness. Richter’s comedic point was that the answer is clear — the owner, because death in a pound is worse than loneliness. Both responses are pretty glib: the sentimentality and the irony exist in a symbiotic relationship.
Similarly “I love irony” is acceptable only when said ironically and “I hate banality” is a deeply banal statement. They are both more palatable as negations — I hate irony and I love banality are at least funny things to say.