Akeelah and the Bee has a character named Dylan, whose father insists that he be Asian and Nerdy and beat the titular character in the national spelling bee by saying that if he comes in second place in anything, he'll be second place for life.
Another Disney Channel example would be Alley Cats Strike. however, despite first guess, the Serious Business isn't so much bowling itself, but rather the rivalry between the city's two schools. Though in this case the True Companions are as bewildered by their schools behavior as anyone else would be.
American Psycho does this with a number of yuppy affectations, but most especially business cards. There's a serious rivalry in Patrick's firm about how good they look, right down to the subtle shades of white and the font. In fact, they're so serious, Patrick kills a guy who has business cards better than him. Or does he??
The Andy Hardy series finds Andy Hardy, a fresh-faced likeable boy in Everytown, America, usually having to deal with exceedingly small-stakes problems that he always treats as Serious Business. In Love Finds Andy Hardy, the big problems are 1) getting a date to the Christmas dance and 2) getting $8 so he can buy a used car to take to said Christmas dance.
In Avalon, the eponymous game is so serious Ash makes a living out of playing it.
Balls of Fury does it with Ping-Pong table tennis... In a ludicrously over-the-top way.
In Band Slam, band competitions are "Texas high school football big."
The sport BASEketball from the film of the same name becomes serious business to many people very quickly, becoming one of the most popular sports in America only a few years after being invented by two drunk guys. And then the plot of the film is based around one of the team owners trying to make it Serious Business, trying to get the rules changed so making serious money is more possible.
As pictured on the main page, Walter in The Big Lebowski has bowling. He's willing to pull a gun over a rules infraction, and he'll even break the Sabbath to prevent a team member from quitting. And the whole story is kickstarted by a petty feud over a soiled rug that really tied the room together.
In the Bill & Ted movies, the music of Wyld Stallyns has become the basis for the entire society of the future, curing diseases, fostering world peace, and improving people's bowling and mini-golf scores.
Mildly averted in Blackball. The film itself is a spoof in which bowling is a very serious business. When the hero sets up a rivalry with the (60 year old) reigning champion and falls in love with his daughter, he wants to show her some of the magic and importance of bowling. Her response: 'I HATE bowling'. He more or less accepts this.
Blackballed: The Bobby Dukes Story does this with professional paintball.
In the DCOM movie Camp Rock 2 there's a song called "Don't back down," which makes a rivalry between summer-camps out to be incredibly serious business. It's hilarious until you realize it's not meant as a parody.
The main character in Carry On in the Legion runs away to join the French Foreign Legion so that he wouldn't get arrested for apparently cheating in a cricket match. Looks like cheating in a cricket match in front of the upper-class is Serious Business.
Celtic Pride is about a couple of Celtics fans who kidnap the Utah Jazz star player so their team can win. In the end, all three men learn to just enjoy the game. That is until football season...
A Christmas Story: Told from the perspective of a child, everything is serious business. When Schwartz issues a "double dog dare," then skips the "triple dare" to go straight to the "triple dog dare," the crowd of boys are suitably impressed by the gravity of the situation. In another vignette, Ralphie decodes Little Orphan Annie's secret message like it's a matter of national security.
In Crossroads, blues music is apparently serious enough to sell your soul to the devil for, and motivation enough to break self-confessed murderers out of custody. The selling your soul is a Shout-Out to blues legend Robert Johnson who claimed to have sold his soul to the devil at the crossroads to play guitar so well.
The Disney Channel movie Dadnapped is all about this trope, in which the main character's father is kidnapped by his fans.
Duplicity plays this straight with the main plot; competition between two cosmetics companies is treated as Serious Business. Competition in the microwave pizza industry is dismissed as silly.
In eXistenZ, people are willing to commit murder over the eponymous video game. This was partly inspired by the trials and tribulations of the director's friend, Salman Rushdie. A major theme of the film is just how fanatically people can react to works of art.
In King Vidor's The Fountainhead, the public views architecture with a fervor combining the World Series, the Super Bowl, the World Cup match, and whatever the Kardashians did last night. Not sure if it's the same as in the novel, but I suspect so.
In The FP is built around the inherent comedy of the gangs of Frazier Park dueling by playing "Beat Beat Revelation." For some reason this is abandoned in the final act, when a duel escalates into standard gunfights and fisticuffs.
Deconstructed in Friday Night Lights with American football. The extreme passion people in Dillon, Texas have for the sport is implied to make things worse for the team, as it is their burden to make the town proud and most of them are fighting enough of their own battles without the pressure of a town's failed dreams on their backs. Also Truth in Television; football is very serious business in Texas and much of the rural South.
Furry Vengeance would have the animals tormenting Brendan Fraser's character because they aren't going to take well of his plans of tearing down their forest for a development.
God of Cookery is a film about a disgraced chef battling to regain his honour.
The crowd is really unnaturally engaged during all of the debates in The Great Debaters, to the point that it's kind of distracting.
In Green Street (or Green Street Hooligans for Americans), a visiting American learns that association football appreciation is Serious Business in the UK, falling into a circle where it leads to brutal gang brawls, mutilation, and outright murder.
Planet Terror: JT, the steakhouse owner, has a falling out with his brother, the sheriff, over his barbeque sauce recipe. Whenever they talk on the phone, the conversation turns to the barbeque sauce in under a minute. After they've both been shot, JT finally tells his brother the recipe, and the sheriff uses his dying breath to promise never to tell anybody the recipe.
The movie Harold & Kumar Go to White Castle, in which White Castle hamburgers are serious business. One other fast-food cook wants to burn down his restaurant for them.
The movie Hatley High, in which chess is very serious business.
The zombie film Hide And Creep has a precious moment of this toward the beginning, where one of the main characters enters a diner and orders Coke, only to find out that they only serve Pepsi. He then goes into a massive pro-Coke/anti-Pepsi rant, finally summing up that the diner was "like red China" for not giving the diners their choice of cola.
In a World......: Voice-over work, specifically for movie trailers, which is treated as far more prestigious than other jobs that use the same skill set like advertising for products other than movies, voice coaching, narrating audiobooks, or voice acting for animation.
In Kill Bill, Hattori Hanzo invokes this trope by name while discussing Japanese pronunciation with the Bride. He also somewhat arrogantly speaks of the swords he makes with absurd reverence, and claims that his best one (which he makes especially for the Bride) is so perfect it could cause Godto bleed.
The King of Kong is about all the drama behind Donkey Kong world records. "Donkey Kong kill screen coming up..." There was even more serious business behind the scenes. Careful editing played up the rivalry and made a less obvious villain out of one of the players.
Bowling seems to be pretty popular for this trope, as Kingpin also did it, what with Bill Murray's character getting his young, upstart rival's hand shoved into a ball return through a "misunderstanding" with some gangsters... who also bowl.
In The Last Starfighter the entire trailer-park drops what they're doing runs over when they hear Alex is about to break the record score on the Starfighter video game. They are all elated when he does, and Alex later tells his mother that this day will be remembered forever in the trailer-park. Possibly justified, as there doesn't seem to be much else to do there, and it's implied they have all played it at some point.
In Mean Machine and The Longest Yard, association football and American football are Serious Business to convicted felons. However, their primary motivation is actually to hurt the guards on the opposing team as much as possible.
The Mighty Ducks: The local newspaper not only covers the games of a bunch of 12-year olds, but features them with headlines, one including a dramatic "Face-Off" of the two coaches before the final game. The villain coach tells his team to intentionally hurt a player on the Duck's team due to him being on the Duck's due to re-zoning. Jesus Christ man, it's a game between 12 year olds!
In Mystery Team Duncan's use of the word "fuck" is considered more distressing than two double homicides.
Brazilian movie Os Farofeiros has a character who takes card games seriously to a violent degree. Once her Canasta (or more specifically, Buraco) partner misses her signals and does a bad play,note that even violated all courtesy/logic of paired games: Going out when your partner has just picked up the discard pile she tackles her to the floor. And after splitting the fight, the woman's husband reveals she stabbed her brother-in-law for turning a natural canasta into a mixed one.
In Pitch Perfect everyone takes a capella far too seriously. Especially Aubrey, though Becca considers it a useless diversion at first. The sequel takes it even further, suggesting that rich eccentrics like to host a capella battles, complete with a Big Board and formalized rules. Though at one key point it's subverted, when Becca reveals her dirty secret that she's been interning for a job after she graduates, the rest of the team says they already knew, and even Aubrey states that she didn't expect Becca to dedicate her whole life to a capella.
In the documentary Please Vote For Me, a Chinese third grade class gets way too competitive over an election to be class monitor. It includes slander, threats and bribery. For third graders. Link to doc.
D Grade suburban cricket is this to Teddy and Colin in Save Your Legs!. To the rest of the team, not so much.
Jack Black's character puts it in exactly these terms in School of Rock: "Now, this is serious business here. We've got a mission. Putting on a great rock show is the most important thing. One great rock show can change the world."
Speed Racer has automobile racing, which has become by far the biggest global sport and has a major impact on the prices of the biggest corporations. Speed even explicitly compares signing with Royalton's company to making a Deal with the Devil.
Hip hop street dancing is Serious Business in Step Up 2: the Streets. This is cemented from the very beginning with a ridiculously dramatic opening monologue. It gets worse within the first 5 minutes, where a subway prank involving dancing is reported on the news as though it was a terrorist attack! (right down to the subway being closed down)
Tag is about five friends who have been playing the same game of tag every May for thirty years straight, and go to great, somewhat dangerous lengths to tag each other. Best exemplified by Jerry, who has never been tagged and uses elaborate disguises and traps to maintain that record.
In Tampopo, most of the characters treat the preparation, serving and consumption of food as serious business.
Even narrower that than. Not simply food, but noodle soup!
The Ten does this in most of its stories. Most of the plots are motivated by people obsessing over fairly ludicrous things. It might just be a statement on people taking religion overboard, but it gets pretty inane. For instance, certain segments hinge entirely on people obsessing over:
A man half-buried in the ground after a skydiving accident.
In A Very Harold & Kumar 3D Christmas, Harold's father-in-law (played by Danny Trejo) takes Christmas and especially Christmas trees very seriously. Naturally the tree he brought is destroyed by Kumar and the title characters have to go out and find a replacement.
In Weekend by Jean-Luc Godard, anything related to the bourgeois lifestyle is Serious Business. Beware not to dent somebody's car. And for some reason everyone carries around a weapon or is insane.
Gently parodied and lampshaded in Whip It; the protagonist thinks rollerderby is a huge deal, but it's mostly because she lives in a small town that she hates and has nothing else going well for her. Her team's coach is obsessed with winning, but the rest of the skaters have a more relaxed view, and when they lose the final, they still celebrate because hey! They made it from last place to the final!
Played first for comedy and then for horror in The Wild Hunt, in which a group of LARPers take the game far too seriously.
The Wizard plays with this trope in that in the world of the film, Nintendo is an integral part of the culture. Everyone knows it, everyone plays, and everyone's plugged in, to the point where "Video Armageddon" is greater than the Super Bowl.
Sometimes futuristic films will be set in a world where a bizarre game has replaced war:
In the original Rollerball, wars have been replaced by a brutal form of roller derby.
In Robot Jox, America and the USSR resolve land disputes not by nuclear war, but by gladiatorial combat between giant robots. The trope is almost inverted in the fact that the bouts are televised and treated like sporting events by ordinary citizens.
Sound of My Voice: played for drama with an elaborate Secret Handshake that is required from all cult members to gain admittance to sermons from the cult's leader. Some sequences of the handshake look like a child's "patty cake" clapping game. It turns out the handshake was invented by a child.
The Caine Mutiny: Played for Drama: The disappearance of a quart of strawberries (which may or may not have never even been loaded to the ship) drives Captain Queeg into performing a full-blown investigation, with punishments (like denying time off) and interrogations (including Perp Sweating) galore. The fact that he places an incredible amount of effort into finding these strawberries instead of focusing on other important parts of managing his ship makes all the other officers believe he's insane and eventually becomes the cornerstone of the defense against the charge for the eponymous mutiny.
Norwegian movie Freske Fraspark (Spry kickbacks): Played for Laughs: A local sportsman wins the national skiing contest, and because he grew up in the border area between two municipalities, both of them claim ownership to him with cataclysmic results. The casualties count, among other things, a dead cow, 20 featherless hens, a broken arm, several bruises and a lot of spilled energy for nothing. The fact that the train stops for two more minutes on one of the stations is counted Serious Business as well.