Daytime television has traditionally been aimed at children and housewives, who were the largest demographics expected to be home during the day. However, college kids, unemployed slackers, and other groups who are home during the day (or have access to a TV during daytime hours) have catapulted certain shows into mainstream appreciation.
Tokusatsu is aimed squarely at kids. However, they cast a lot of pretty-boy actors to appeal to the mothers of the aforementioned kids, who often watch the show at home with their children; this occasionally applies to older sisters as well. The Japanese have dubbed thisnote specifically, drawing in a female audience by casting handsome male actors "the Odagiri effect" after Joe Odagiri, star of Kamen Rider Kuuga, one of the first observed instances of this trope and launcher of a fair bit of Follow the Leader. It also works the other way around, with fathers and older boys being drawn to these shows thanks to the cute young singers and gravure swimsuit models who play the female leads. A second periphery demographic is the small but solid overseas fanbase, who tend to be in their late teens or mid-20s, overlapping somewhat with the Power Rangers fandom as well.
An episode of Samurai Flamenco actually discusses this phenomenon. Masayoshi's manager books him for a guest spot on a Super SentaiExpy, and claims that it will boost his career since Toku shows are watched by a large number of women with disposable income.
It should be pointed out that some of the Super Sentai and Kamen Rider entries into this trope may be due to air times. Prior to the mid-2000s, they were largely seen as family shows (for Americans, think of them in the same way as The Incredible Hulk TV show and you're not far off). Originally they aired in an evening time slot, so it would be perfect time for family viewing. Around 1997 note for Sentai only, Kamen Rider first aired in the time slot in 2000, replacing Moerou! Robocon., they were moved to 7:30AM and 8:00AM on Sunday mornings and then to 9:00AM and 9:30AM two decades later, often seen as the Saturday Morning Cartoon equivalent.
Disney XD shows are aimed at preteen boys, but its cast of good-looking guys like Logan Miller, Billy Unger and Leo Howard have certainly attracted many female fans. Likewise, it also attracts many older male fans who are into the female stars like Olivia Holt, Kelli Berglund or Paris Berelc.
SpongeBob and FOP are also longrunners, so it's also likely that young adults have grown up with these shows and still watch them.
This was Lamp Shaded on Liv and Maddie, where it's revealed that younger brother Parker and his best friend (and a lot of his dojo) are fans of a show called "Linda and Heather."
The idea of the Sci-Fi Channel (or SyFy now) having a mostly young male demographic is increasingly fallacious, which the execs seem to have some difficulty recognizing; when confronted with the fact that many of their viewers are women, David Howe acknowledged that "almost half of our audience is women, thanks to shows such as Ghost Hunters that attract more women than men", completely ignoring the fact that many of their scripted shows (Farscape, The Invisible Man, the various Stargates, Battlestar Galactica (2003), etc.) had/have significant (if not overwhelmingly, or at least more involved in online fandom) female audiences.
Kika, a German kids' channel, has a mascot called Bernd das Brot (Bernd the Bread). The pessimistic loaf of bread became a cult favorite with young adults and teens in Germany. Kika started airing a looped program with Bernd instead of static after 9 P.M, attracting many insomniac young viewers.
Likewise with queer characters in Soap Operas, in terms of attracting LGBT viewers who normally don't watch them. The After Elton website, has a section dedicated to shows like this called "Gays Of Our Lives".
Soap Operas tend to be aimed at middle aged women. But they become quite popular among college students. The joke is that the televisions in student houses don't get many channels so the students end up watching soaps all day.
America's Next Top Model as well as any of the other Top Model shows have enough Fanservice to attract male viewers.
Project Runway to a lesser degree for similar reasons.
The Price Is Right was obviously designed to appeal to housewives, who would do most of the shopping for household items. Over the show's long history, however, it has garnered interest from just about every viewer demographic.
Bob Barker noted that the show got a lot of college fans after he was featured in Happy Gilmore and beat up Adam Sandler.
Wheel of Fortune and Jeopardy! likewise grew from mostly housewife appeal to pretty much universal. Especially since the mid-90s or so, they've taken to having more college-age students.
In the UK, Deal or No Deal was formerly the show of choice, possibly due to the presenter (Noel Edmonds) having presented 90's show Noel's House Party. Probably more down to the fact that he's able to make a show about someone opening boxes seem quite tense and nail-biting. Even when all the big prizes have gone.
The Food Network's initial run of Iron Chef carried advertisements generally aimed at over-40 housewives, who were Food Network's primary demographic at the time. When the show was adopted by younger viewers due to its competition aspect and the Narm Charm of its presentation, Food Network was caught flat-footed and took a lengthy period of time to properly capitalize on the show's success by making it a centerpiece of their lineup. Rapid Network Decay soon followed.
Anthony Bourdain's first show was also adopted by a younger demographic than originally intended.
Teletubbies is a show aimed at extremely young children, but it became famous for attracting the attention of college/uni students and druggies, all of whom were often watching television in the middle of the day. The show's baffling and surreal nature, combined with its bright colors and hypnotically repetitive nature, made the show enjoyable with the right amount of irony or chemistry.
Ragdoll Productions' other show, Boohbah, has fans in their early teens, who probably like the show for its' surrealism.
In the Night Garden is arguably even more cutesy, surreal and coy than Teletubbies, and makes perfect hangover viewing, or if you are so inclined, watching it stoned or tranquillised is amazing.
Shows aimed at older children. Raven is surprisingly popular among adults.
The Sarah Jane Adventures is watched by many adult fans of parent show Doctor Who. It was particularly popular among long-term fans of the show who thought that it had many nostalgic elements of the twentieth-century show that the revived one changed (twenty-five minute episodes with frequent cliffhanger endings, less focus on romantic shipping, less angsty regular characters). When you consider that the show has Torchwood references, that may be intentional.
Doctor Who was originally intended as a show that would teach history to kids, but when it started going more overtly science fiction (in its second serial no less) it started to bring in a lot more adult fans who would watch with their children, not to mention the kids who grew up and yet stayed with the show into adulthood thanks to its Long Runner status. It's a matter of (at times quite heated and interminable) debate, however, whether the show is a 'family' show (i.e. intended for both kids and adults from the start), a kid's show that happens to claim a strong Periphery Demographic among adults, a kid's show which eventually became a family show or something else entirely. In short, Doctor Who can be best be summed up by three words: Multiple Demographic Appeal.
This trope was the reasoning that the BBC used to explain the extreme, disproportionate popularity of the Fourth Doctor as compared to the other classic Doctors. Philip Hinchcliffe and Tom Baker deliberately developed the character to appeal to college students and hip, childless young adults, who would not normally watch a children's show, as well as to the usual demographic of kids and parents. This was achieved by making the character darker, more morally and emotionally complex, and focusing on his fear of the monsters more; as well as going with a 'Bohemian' aesthetic which enabled plenty of Genius Bonus and counter-culture compatible quirks in addition to the expression of trendy Chaotic Good politics (coming along just as punk began to happen).
Classic Doctor Who also tended to treat the Doctor as a rather asexual character, often in order to discourage any suggestion of "hanky-panky" between himself and his (usually) young, attractive female companions and thus prevent the Moral Guardians from complaining. This had the largely unintended side-effect of generating a large fandom for the show among the LGBT+ community, who found the idea of a TV hero who was largely coded as non-heterosexual quite appealing.
Although Beakman's World was generally aimed at 9-to-14-year-old school kids, high schoolers and college students liked it too. Maybe it was because they finally got what they couldn't get in middle school; maybe it was because the main character looked like someone who'd do drugs; maybe it was the assistants (no, not the rat); or even a combination of all three.
Similarly, Bill Nye the Science Guy still has a significant following among young men, which may have been a factor in creating a similar series more directly targeted at them.
The Nostalgia Filter probably has a lot to do with this, since both these guys have been around since at least the early '90s. Who knows, it might even appeal to middle-aged/elderly Baby Boomers who remember Mr. Wizard.
In Seattle (where the show was filmed), a large part of the audience were older adults who really missed Almost Live!, where the Science Guy and the other cast members got their start.
The children's TV show LazyTown is also known to be popular with teenagers and young adults as well as parents, possibly due to its quirkiness and Large Ham villain. Though given Sportacus's and Robbie's tight pants we can be reasonably sure that some of the adult appeal is deliberate.
Though some of thesongs are catchy as well. "You Are a Pirate" and "We Are Number One" are the only reasons some people have even heard of this show.
iCarly started off aimed at roughly the 8-14 market, but ended up being a massive hit in all the children and teen demographics (from young kids to mid teens). Since people caught on to the massive amounts of Getting Crap Past the Radar included, it's now a big hit with adults and college viewers as well.
Many parents and adults tend to view Yo Gabba Gabba! as a Guilty Pleasure, although some of its appeal is from the show's baffling ability to somehow convince popular indie rock bands like Low, Mates of State, Hot Hot Heat, The Shins and Of Montreal to appear as musical guests.
It helps that the show was produced by a member of the Aquabats.
A growing number of Western fans in their 20-30s grew up watching Power Rangers. The fact that they brought back Jason David Frank (as a regular cast member for season 12) and Johnny Yong Bosch (in a guest spot for the 15th anniversary) would suggest that the producers are well aware of the older Power Ranger fans.
The 20th Anniversary series Power Rangers Megaforce looks to be catering to this demographic a bit as well as it will feature appearances from past Rangers possibly including Jason David Frank.
The Canadian TV series Trailer Park Boys is very popular with both criminals and police officers. The former are able to identify with the main characters (the producers even describe the show as "Cops from the criminal's point of view"), while the cops enjoy seeing depictions of what they have to deal with in their jobs.
It's also popular with both the lower-class demographic it depicts and more well-to-do people who find the portrayal of their lifestyle hilarious.
Word on the street has it that the live-action The Dresden Files TV series was cancelled because, while it had an active fan following, said fan following was mostly older women who didn't mesh with the rest of the Sci-Fi Channel's young male demographic.
As for sci-fi examples, Stargate Atlantis was cancelled to make way for Stargate Universe so TPTB could appeal to a younger male demographic instead of SGA's (very large) female fanbase.
Considering the copious amount of almost soap-operish melodrama (at least in the opening episodes), it seems that SyFy have decided to try for Multiple Demographic Appeal with the show.
TPTB claim that the cancellation of SGA and the launch of SGU weren't direct causation. They have not convinced many fans that this is true.
The Vision Ongallery theme tune, so iconic it penetrated a national consciousness, can only be intended for the periphery demographic, as the intended audience was deaf children.
Sesame Street intentionally invoked this trope, in order to create a show that kids and parents would watch and enjoy together. This kids show grew its following gradually; when the original kid viewers grew up to be adults, they would subsequently watch the show with their own children.
Choujinki Metalder, the sixth Metal Heroes show, attracted a primarily older fanbase instead of its intended young audience due to its dark and complex storyline compare to previous Metal Hero shows. As a result, it was canceled at the end of its third course, with only 39 episodes instead of the usual 50.
Top Gear is a Petrolhead Show, but there are plenty of people who watch it without knowing much about cars, simply because it's hilarious, and it doesn't hurt that the film crew is great at making everything look good.
Both the producers and the star, Jeremy Brett, were surprised to learn that their 1984-1994 Sherlock Holmes TV series adaptation was very popular with kids, who seemed to see the lead character as a Super Hero. As such, Brett got permission from the granddaughter of Arthur Conan Doyle to have Holmes beat his cocaine addiction and bury his needle.
It's a little hard to find The Golden Girls' original demographic. Even during its debut it was very popular with younger demographics (and still is). When asked why, I think Betty White said it best, "Because it's funny!"
War miniseries like Band of Brothers and The Pacific, in theory and according to mainstream media, are generally geared at middle-aged-to-older men (Seth Meyers, making fun of Eric Massa, accused of groping a staffer at his fiftieth birthday party: "That's not what happens on 50th birthdays. On my dad's 50th birthday, we got him a gift certificate to Morton's and a Band of Brothers DVD"), including those who possibly served. However, they tend to have very strong fanbases of young women in their teens and twenties, partially because of the wealth of young men in uniform and the many shipping possibilities. However, many seem to have genuine interest in the history as well.
Not to mention that said earworms are often played in teenage/adult clubs in Belgium.
Another good example from the creator Studio 100 (the same ones who were responsible for Kabouter Plop above) would be Samson en Gert. Although the show was mainly made with kids in mind, the adult setting and sitcom-like scenarios also attracted pretty much everyone who was not in the intended demographic and started becoming one of the more adult-oriented programs on the channels where it aired.
The British teen drama Skins has multigenerational appeal thanks to its excellent writing and acting. In fact, adult fans probably outnumber teen fans outside of Britain.
Wishbone was aimed towards kids seven to fourteen, but it gained a lot of popularity from teenagers and adults, as well as many literature fans.
Horrible Histories, the live-action adaptation of the classic kiddies' history series, airs on the British equivalent of PBS Kids and is theoretically aimed at 6 to 12-year-olds... which in practice hasn't stopped the show's writers and performers from slyly directing it squarely at older teens/adults, who've responded in droves.
MTV's Teen Wolf has attracted a not insignificant adult gay following. Considering how much time the many attractive guys on the show spend shirtless, and the show's casual inclusion of a gay character and gay themes into some of its episodes, this may not be entirely unintentional.
The CBC has a significant American audience, thanks to the Canadian population living for the most part near the U.S. border. CBC stations can be picked up over the air in most cities bordering Canada, and the CBC is even carried on some cable systems in markets near the Canadian border.
Barney & Friends, despite its significant Periphery Hatedom, has a cult following that's just as significant. Among other things, his own wiki is one of the biggest wikis for a franchise with more than 2000 pages as of this writing, and many have given requests on YouTube for specific episodes, appearances etc. Then again, much of this is due to childhood nostalgia, adults who prefer the show as a less-violent alternative to other kids' shows on the air and/or are checking out some of the earliest TV appearances of Demi Lovato and Selena Gomeznote who were actually standing in line next to each other when they were auditioning for the show. Ironically, most of the people who grew up with said season grew up with these artists' music.
Even though the humor of the shows would likely go well over kids' heads, it's not too uncommon to see late elementary school/early middle school age kids watch Seinfeld, Married... with Children or Full House reruns.
Friends is really popular with teenagers even 10 years after the show has ended, but it helps since most of them were actually born when the show was still on the air.
Dexter has an enormous female fanbase, probably because most women find his "damaged yet very mysterious" nature charming.
The Big Bang Theory is one of the most oddest examples of this trope. Even though most of the characters in the show work in a university, and it features a lot of nerd and geek references, it was always aimed at adults aged 18-49, like many sitcoms of its kind. However, since then, the show has accumulated a huge following with nerds and geeks, who not only appreciate the many science fiction and comic book/superhero references, but also can relate to many experiences the characters go through. It's got to the point where it's so huge, that the show itself has become a part of the nerd and geek entertainment.
Game of Thrones and A Song of Ice and Fire are very popular among adolescents. It's mainly due to growing up in the social media that didn't exist when shows like the Sopranos, The Wire and Oz were on the air. Basically, the exact opposite situation of Periphery audience The Hunger Games has received.
The BBC's The Musketeers has gained a considerably large female fanbase in many parts of the globe where it airs, especially in the States and Italy, where cast member Luke Pasqualino hails from. And despite the fact that it airs in the UK after the watershed and that the show gets much darker with the second season, it hasn't stopped it from being popular with families with pre-teen offspring as well.
Vijf TV has women as its main target audience. Its first broadcast however was that of a soccer game. The CEO did this on purpose in the hope of attracting male viewers to their network. There is as of yet however no information that concluded whether or not it worked.
A fair number of The Walking Dead fans seem perfectly content to watch the show with their middle or even elementary school-aged children, despite the extreme violence, TV-MA rating, and the fact that Robert Kirkman, creator of the comic book the show is based on, has been outspoken about how the show is not appropriate for children nor intended for them.
According to the fan section of the PBS website for The Noddy Shop, most of the viewers of the show were surprisingly not in the 2-to-5 range it was aimed at, but rather in the 9-11 range. It helps that the scenes inside the shop with the toys were very interesting and hilarious, and that DJ and Kate, two of the main kids in the show, were around this age. It was also big with adults, due to its nostalgic 50's theme and some of the songs being inspired by Grease.
Odd Squad has a small fanbase of teens and young adults. The show has even took mention of it, putting in adult references to things like Sherlock Holmes, and airing "License to Science", which was a Season 2 episode where the major plot point was Oona getting her license at the DMG (the Department of Motorized Gadgets), something many teens can relate to. Despite this, Word of God has stated he likes the kid fans of the show better than the adult ones.