What makes me inclined to assume that the reason that these things can't really mean anything to the kids because they get in the way of Lynn being a damned big shot is this seemingly unrelated strip in which Elly resists Lizzie's evil and criminal attempt to waste her mother's precious time by filling her important brain up with meaningless trivia about unimportant children who can't help our tragic moron hero in her quest to be the bride at every funeral and the corpse at every wedding. We evil, hating picky-faces who hate humor and want Lynn to suffer some cruel and arcane torment see a small child trying to catch her mother up on things that mean something to her so that Mommy might have some sort of idea of what goes on in her children's lives. What we fail to realize is that Elly will always be too important to waste her precious brain-power on irrelevant and unimportant static about what can't matter, it must be utterly unimportant to anyone...especially to the person it's actually happening to.
The fun part of this is that after years of telling Lizzie that nothing she does can mean anything to her and pretending otherwise is a selfish lie she tells herself because she hates her poor mother, the slobbering half-wit cries a bucket of stupid tears because Liz went to someone who treated her problems as if they were real with said problems instead of to a self-important nincompoop who'd talk over and down to her. Similarly, we have to contend with dumbass Elly not understanding why the Martian behaves as if all of these silly concerts that get in the way of her poor misunderstood mother doing things that really matter because she's doing them behaves as if her fair, firm, kind and loving mother is a self-absorbed wingnut who can only value whatever time-wasting bullshit she happens to be doing at any given moment.