The thing about good comedy is that it's usually got more content than you think. The best comedy is about something more than making you laugh; it is rooted in character, and often rooted in something that is painful or difficult to talk about.
The World's End (which, by the way, was very good) is about both the classic conundrum of adults returning to the old haunts of their youth to find they don't fit in there anymore, and also about the tension between the freedom of youth and the burdens of responsible adulthood. Thankfully, it explores these themes in all their complexity, rather than making pat pronouncements.
Also, a lot of mandroids get bashed into goo.
I think this is true (the comedy has content part, not the robots bashed to goo part) of the best comedy roleplaying games too. Paranoia is about living in an Orwellian futuristic dystopia, and more specifically it's about roleplaying games themselves -- lampooning the "old school" style games where the GM was supposed to randomly visit misery and death on the characters. Many of the old Paranoia adventures even reference specific games.
Fiasco is a bit of a fringe case, because it straddles the line between screwball comedy and high-pressure drama. Although the tone of the game is usually over the top, and the overwhelming mechanical result of play is a series of hilariously tragic / ignominious endings for the players, it would be possible to see a Fiasco game played very seriously.
What I'm getting to here is that a good comedy game has a lot in common with HTHD play. Good comedy is about characters, the things they want desperately, and the actions they take to get them. All of that is true of drama too; the difference is in the tone. Good drama games and good comedy games have an underlying theme they're portraying. Comedy does not necessarily equal random goofiness.
I think it's significant that at least a couple of the example Series given in Primetime Adventures are comedies, especially the children's show "Moose In The City". The tools and the rules are the same, it's the authorial intent of everyone at the table that matters.
I think it's actually a potential pitfall of HTHD play that you begin to take yourself and your games too seriously at the table. Powerful, dramatic scenes are well and good, and for those of us that enjoy that kind of play, they are rewarding like nothing else. But there is also room for different kinds of games that aren't doom and gloom, aren't for the-world-will-be-doomed-if-we-fail stakes, aren't your usual cuppa. I found it very rewarding to deliberately aim my Firefly game toward a more upbeat and optimistic ending than my games usually have.
Mixing up the tone and content of your games is always a good idea, whether it's scene-to-scene, episode-to-episode, or passing from one game to the next. A one-note game is ultimately as unfulfilling as one with no content at all. Roleplaying can and should embrace all genres, borrowing whatever tricks it can to grow and become richer and more complex.
Why not play a comedy?