Brazil's World Cup bid said the country would spend less than $1 billion -- mostly private funding -- to renovate seven stadiums and build five new ones.
The renovation of Mane Garrincha, a stadium built in 1974, has already cost $750 million. The cost of completing all of the stadiums is on track to exceed $3 billion -- all of which has come from taxpayer dollars.
That cost has stalled public works projects that were intended to be completed in tandem with the World Cup preparation.
Brazilians have adopted a new slogan: "Nos não precisamos da Copa do Mundo," or "We don't need the World Cup."
Brazilian demonstrators took to the streets to protest the spending, which has led to deprioritization of government services Brazilians depend on, including public transit and education.
"We're massacred by the government's taxes -- yet when we leave home in the morning to go to work, we don't know if we'll make it home alive because of the violence," said Maria Claudia Cardoso, who protested in Sao Paolo.
"We don't have good schools for our kids. Our hospitals are in awful shape. Corruption is rife. These protests will make history and wake our politicians up to the fact that we're not taking it any more."
The protest sparked security concerns during the Confederations Cup over the weekend, and a worry about future security concerns as Brazil prepares to host the international soccer tournament but also a visit from Pope Francis in July and the 2016 Summer Olympics in Rio de Janeiro.
For World Cup security, it has contracted iRobot to provide 5,000 camera-equipped robots. The bots usually cost between $100,000 and $200,000 each, plus the cost of servicing the units.
The government is also spending $900 million on drones, helicopters and surveillance and equipping Brazilian police with facial-recognition camera glasses to make the cup the most secure sporting event in the world.
The protests are the country's biggest demonstrations since the end of the country's 1964-1985 dictatorship.
The initial protest was in Sao Paolo to demonstrate against an increase in bus and subway fares and had 5,000 participants, followed by a widespread bus-driver strike. Now, worsening government services have led the demonstrations to spread across the country.