They'll pay hundreds of dollars to an illegal ticket seller. They may unknowingly buy fakes, and be turned away at the door. The extremely desperate have even jumped a stadium wall.
Igor Guerra, a 21-year-old Brazilian law student, held a sign in three languages saying, "I buy tickets," as thousands of people marched into Rio de Janeiro's Maracana stadium late Sunday.
Wearing an Argentina team jersey, Guerra said he was willing to shell out $250 to watch Lionel Messi in the legendary stadium against Bosnia.
He knew it was an illegal venture that football's governing body FIFA frowns upon.
But, he said with a shrug, "I don't like a lot of things FIFA does either."
FIFA has tried to make it hard for people to resell tickets. They are non-transferable and bear the buyer's name. They can only be resold through an official online platform.
But in general the identities of spectators are not checked as they enter the stadiums.
- Sneaky fans -
One group of four crafty Argentine fans who drove 2,500 kilometers (1,500 miles) from Cordoba to Sao Paulo snuck their way into last Thursday's Brazil-Croatia opening game.
They said they walked into a five-star hotel and convinced the receptionist they were representatives of an international company with commercial links to FIFA.
The woman, without asking many questions, handed them VIP tickets to the game, said one of the young men, who refused to give his name.
"There was sushi, champagne. And Ronaldo 'Phenomenon' was there," he said, showing pictures taken with his cell phone of the game and of him and his three friends next to Brazil's 2002 World Cup winner.
"Not even Maradona could get in," he said laughing.
But they were thrown out before the end of Brazil's 3-1 victory. The flip-flops they were all wearing gave them away.
For the Argentina-Bosnia game, they had to settle with watching it on television at a bar near the stadium -- but with no beer. A law bans alcohol near the stadium on game day.
- $1,600 tickets -
Other Argentines couldn't stand missing the game, and didn't let the rules get in their way.
A group of around 30 people wearing Argentina's colors, one with a Diego Maradona wig, jumped a stadium wall and crashed through a gate to flood into a restricted area -- all captured in an amateur video posted online.
Nine of them were arrested, taken before a judge and released.
The rest likely fulfilled their dream of seeing Messi score a wonder goal in the 2-1 victory against Bosnia.
Police stopped more shenanigans outside the Maracana.
Three Britons and a Frenchman were arrested near the stadium as they sold tickets for the game. Police said they had seized $6,000 and 14 tickets.
Fans risk getting ripped off when they buy tickets from unauthorized vendors.
Days before the World Cup kicked off, police arrested eight workers from the consortium that refurbished the Maracana who were selling tickets for some $200 a pop, around twice their face value.
In May, a Rio firefighter was arrested for making fake tickets, including some for the final priced at $4,000.
At the opening game, around 50 people were prevented from entering Sao Paulo's Corinthians Arena because they had fake tickets, FIFA said.
Outside the arena, a Mexican man had told AFP last Thursday that he had sold three tickets for $2,500.
In the western city of Cuiaba, tickets for the Chile-Australia game were being sold for $1,600. Chile won 3-1.
"They are very expensive," Chilean fan Carla Jimenez said. "But it doesn't matter. I want to get one. It's my life dream to see my team at the World Cup."