Given that its status as one of the longest-running primetime series ever, with probably the most sustainable DVD fanbases of any show to last more than ten seasons, it makes sense that Fox would celebrate the recent 20th anniversary of The Simpsons with some kind of promotional DVD. Complete season sets of the show have been appearing once or twice a year for the better part of a decade, so obviously the release of next-in-line Season 13 wouldn’t cut it as a promotional tool.

Instead, Fox has skipped ahead to the near-present: the 2008-2009 season of The Simpsons, that historic 20th, jumped the queue and onto shelves. In their rush, though, they’ve left out just about everything that’s made Simpsons DVDs, even of lesser seasons, endlessly collectible. The first 12 season sets contain, at minimum, audio commentaries on every episode and outtakes in various forms. The 20th season features none of these. It has all of the episodes from season 20, unadorned, and a “sneak preview” of Morgan Spurlock’s retrospective on the show, which actually aired before these DVDs were released.

This combination of opportunism and sloppiness is faintly mind-boggling. If Fox was looking for an easy cash grab without much effort, it seems like the best option would be some kind of best-of compilation: four discs of episodes from all 20 seasons, say. It wouldn’t necessarily entice the hardcore Simpsons fans, but it could serve as an overview for casual viewers who might want to re-watch some classics without buying a dozen or two boxed sets.

Instead, Simpsons fans have the opportunity to watch episodes that, in some cases, were just rerun over the summer. All that remains on the discs is the show’s late-period inconsistency. Some episodes display structural inventiveness, like the puzzle-centric “Gone Maggie Gone”, or canny pop-culture riffing like “Lisa the Drama Queen”, a heartfelt spoof of Heavenly Creatures. Others fall back into bad habits: season opener “Sex, Pies, and Idiot Scrapes” has both Marge and Homer getting new jobs and, get this, Homer’s has ample opportunity for grotesque, over-extended slapstick gags involving tasers and bullets (he’s a bounty hunter, not to be confused with the times he became a sheriff, or a vigilante, or a biker, or a secret service agent). The show also continues to build episodes around visits to new locations (“In the Name of the Grandfather” sends the family to Ireland) and anthology pieces based more on by-now worn out novelty than wit (“Four Great Women and a Manicure”).

More vexing, 21st century The Simpsons isn’t always even coherently inconsistent; it’s not simply a matter of good episodes alternating with mediocre. Sometimes, episodes feel like they’re written and produced without much knowledge of each other, repeating themselves within seasons: “Idiot Scrapes” opens with a bunch of funny Irish gags at a St. Patrick’s parade, and a dozen episodes later we have more Irish stuff in “Grandfather”.

Other repetition is even less concealed. Early in the season, two episodes in a row, “Lost Verizon” and “Double, Double, Boy in Trouble”, have almost the exact same story thread, with Bart happily separated from his family and then learning to appreciate them in their absence. Nevermind that both episodes, especially “Double”, knock off the classic episode “Burns’ Heir”, because after 400 episodes, a feat unmatched by any sitcom of this quality, the show is bound to encounter its own tracks. In fact, both episodes are pretty funny. But a peculiar grab-bag approach places them not only in the same season, let alone one after the other.

Still, the show’s more erratic years represent less a betrayal of its eight or nine years of unfiltered genius than a settling into more typical sitcom groove. That hit-and-miss quality would be a lot more interesting, as it is on some of the recent season sets, with greater context coming from commentaries or retrospectives sorely lacking from this commemorative yet empty set. Why not at least include a longer version of Spurlock’s fluffy but entertaining documentary, rather than a shorter preview? It doesn’t even make sense as promotion, since the TV special has already aired to decent ratings.

The Simpsons has been a commodity for Fox since it premiered; merchandising has ebbed and flowed over the years, but little has matched the onslaught of chintzy consumer products circa 1990, before the show even reached its creative peak—before, really, anyone could’ve predicted the heights of that peak. Two decades on, The Simpsons sustains its ability to make us laugh—and occasionally, to rip us off.