“If this was an R-rated comedy, and they put all these set pieces together like the poker, and the cars, and the Vegas of it all, no one would buy this movie,” said Hamish Linklater, an actor and playwright.

It was Friday night in Las Vegas and Mr. Linklater was standing inside Lavo, a dark, chandelier-filled lounge at the Venetian Resort. About a hundred people had gathered for a star-backed charity poker tournament hosted by Ben Affleck — with Jennifer Lopez at his side — during the Formula 1 Grand Prix Weekend, an event that culminated with one of the nearly two dozen similar races that determine Formula 1’s world champion.

Organizers spent $500 million on the Las Vegas race, which was the first of its kind in the city in decades. The race — which was won by Max Verstappen — drew celebrities, athletes, and moneyed spectators to watch drivers zoom around the famed Las Vegas Strip turned racetrack, and attend extravagant parties. Between the roaring cars, marquee names, and lucrative branding opportunities, it was over the top, as Mr. Linklater suggested, even for Las Vegas, a city founded on diversion.

The poker tournament opened with a reception at Lavo, and then moved upstairs to a side room for the games. Guests, which included Jon Hamm, Jimmy Kimmel, Colton Underwood, James Marsden and Tobey Maguire, spent about an hour drinking champagne (served by a woman dressed as a peacock) and eating Wagyu sirloin and Australian rack of lamb.

The guests then played rounds of poker before stepping out to a terrace at about midnight to watch racecars hurl down the Strip during the qualifying round of the F1 race. (Proceeds from the tournament benefited the Eastern Congo Initiative, a charity founded by Mr. Affleck, which provides humanitarian assistance for the people of Congo.)

Mr. Affleck said he was struck by the influx of people. “I’ve never seen Las Vegas like this, so full,” he said, after posing for pictures. “I’ve never had so many celebrities and high-rollers be like, ‘Can you get me a room?’” said Mr. Affleck, who frequently visits Las Vegas.

Mr. Hamm, standing with his wife Anna Osceola, said he got into F1 as a child. “I loved collecting all the cars,” he said, adding, “Americans are just now discovering it, even though it’s been around for so long.”

Mr. Kimmel, the television host, however, found the entire affair to be a headache, a sentiment echoed by some locals. Ubers and taxis couldn’t get to some locations, and crossing the street near the Strip was difficult.

“It’s a little crazy out there,” he said referring to the Strip, which was shut down for long stretches during races and practices. “The driver who picked us up from the airport had no idea where to take us.”

But Mr. Kimmel said he is not really familiar with F1. “I am sure I would get into F1 if I watched three episodes of the Netflix show, but I’m really busy,” he said, referencing “Formula One: Drive to Survive,” the documentary series that follows F1 drivers, which many attribute to fueling American interest in the sport.

Despite the popularity of F1, however, there were questions about how the weekend would be received. The eventual winner, Mr. Verstappen, had critiqued the event as “99 percent show and one percent sporting event.” (After his win, he changed his tune, chanting “Viva Las Vegas” in his racecar.) Early ticket sales did not meet expectations, and an early practice round had to be canceled because of a hazard on the track, which led to a lawsuit from ticket holders.

But the fans, brands and public figures still showed up. More than 300,000 people attended, and Formula 1 estimated that the event would have an economic impact of $1.2 billion to Las Vegas. American Express gave out F1-themed friendship bracelets and fanny packs to cardholders, Sotheby’s hired James Corden to help auction off used F1 racecars, and T-Mobile branded the Las Vegas Sphere. Patron had a booze-fueled party headlined by Fisher, the Australian D.J., at the nightclub Hakkasan.

About four hours before the race was scheduled to begin, huge crowds of people, including Rihanna, David Beckham, Brad Pitt and Gordon Ramsay, packed into the Paddock, the working area of F1 next to the track where the cars are kept, drivers prepare for the race, and the engineering teams are based. The Paddock also had a premium hospitality area known as the Paddock Club with a rooftop deck with wide views of the track and private, premium suites.

Celebrities and sponsors inspected the cars up close and watched engineers run through practice drills like changing a tire in seconds. Bars set up outside the track served espresso martinis and champagne, and an Elvis impersonator conducted weddings and vow renewals in a makeshift chapel. Nearby, couples posed for pictures with a racecar decorated with the sign, “Just married.”

“Everything is a shock to me right now,” said Will Claye, an Olympic track and field athlete. “My mind is blown. I thought they just drove, but there are all these people managing all these details and everything is thought of in terms of milliseconds.”

Other F1 events have been held in similarly opulent destinations and Mr. Claye said the location of the races are part of the appeal. “You have Miami, you have Monaco, you have Vegas, these are places you want to go regardless,” he said. “So when they have F1 with these cars, and how much they cost, you’re like I’m going.”

Alex Claremont-Diaz, an actor who starred in the romantic comedy “Red, White, & Royal Blue,” said being around these sophisticated cars was nothing new. “My dad has a body shop, and I grew up in body shops, so this is very normal for me,” he said.

But seeing them race around a place like Las Vegas was new. “You just hear zoom, zoom when the cars go past you, and it’s so sick,” he said.

He was with Madeleine White, a social media influencer who has more than 4 million followers on TikTok. “I attended the Ferrari fashion show in September and got to know the team, and they asked if I wanted to come to Vegas with them,” she said. “Of course, I said yes.”

The race began about 10 p.m., and celebrities like Patrick Dempsey, Paris Hilton and Usain Bolt, filed into suites to watch the main event while drinking from an open bar and dining on items like lobster and steak.

While most of the notable names were spectators, some were enlisted in the festivities. Donny Osmond sang the national anthem and Justin Bieber stood at the finish line and waved the black and white checkered flag.

Kylie Minogue, the Australian singer who was performing at a party over the weekend at Voltaire, one of Las Vegas’ newest nightlife venues, where she is also doing a residency, had the opportunity to ride around the track at speed, before the race.

“I was screaming my head off. Tiny me in that car!” she said. “I was safely buckled in, but I was being thrust around, and it was a real thrill.”

It gave her a chance to take in all the crowds around the course. “It was a lot of a lot, which is Vegas.”