It is stupid; it has Elly marvel that Mike cleaned something of his own free will.
Panel 1: As Elly buckles herself into the front seat of the hoverwagon. John thanks her for bringing him the spare keys; Elly says it was no problem because Lizzie enjoyed the taxi ride.
Panel 2: As they drive away from Big Ugly Grinning Sun carwash, John tells us that the attendant will return his car keys as soon as they clean out the central vacuum system.
Panel 3: Mike pops in to tell John that he's really sorry. John's response is to sit there scowling; since he doesn't believe in honest mistakes because he's a self-absorbed, self-pitying dick, he won't allow things to blow over.
Panel 4: Elly tells John "Don't be mad at him; he didn't suck up the car keys on purpose. Besides, there's a positive side to what happened."
Panel 5: The reverent tone she must be using when she says "Our son was willingly cleaning something" gives John pause.
Summary: We sure do have an absurdity-rich environment today. Not only does John have to wait to get keys that couldn't have been sucked up even if he was as careless with them as he was, we get Elly of all people telling someone that a child didn't do things on purpose. Thinking that her children plan to make her day worse is what she is, what she does and how she lives. Also, Elly's life is so boring, a cab ride to a gas station is a treat.