The Confederations Cup is a dry run for the 2010 World Cup
Sepp Blatter has suggested that unsold tickets for Confederations Cup matches should be given away rather than have empty seats at game.
The Fifa president spoke a news briefing on Monday after disappointing crowds marked the opening day.
Neither of Sunday's games attracted capacity crowds.
"I had a meeting with the organising committee this morning, and I think they should have done a little bit more to bring more people to the stadium.
"They could have given the empty seats at Ellis Park to the boys and girls who had taken part in the opening ceremony.
"They could have watched the match. There must be some action taken for the rest of the competition. To have half-empty stadiums is not Fifa.
It is up to the organisers, the local media, to get the message across
Fifa president Sepp Blatter
"They have to do something about it. We know that the prices of the tickets cannot be too high, but bring the young people or the poor people into the stadium, and nobody will be offended by that."
Blatter added: "We were not happy with the crowd at the opening match (South Africa v Iraq) or on Sunday evening when the European champions Spain were playing New Zealand in Rustenburg.
"It is up to the organisers, the local media, to get the message across."
Meanwhile, the BBC's Piers Edwards reports that the opening day of the Confederations Cup received mixed reactions in the host nation from fans and media alike.
The media was effusive in its praise for the opening ceremony, describing it as 'slick' and 'spectacular'.
Yet the national team was not treated with similar enthusiasm after their 0-0 draw with football lightweights Iraq.
"Bafana miss but SA scores," proclaimed The Star following Sunday's Group A game against Iraq.
"Welcome to our World," announced The Sowetan, "Pity Bafana didn't come to the party."
But some fans were unhappy with the lack of food stalls inside the ground, others with the confiscation of their food on the way in, yet the greatest bile was reserved for the park-and-ride scheme.
Four park-and-ride schemes were in place and although three appeared to proceed without any problems, the situation at Wits University was not the same.
"We got to the park-and-ride two hours before the opening ceremony which was very important for us, so missing that because of the enormous queues was a disappointment," Selvan Moodley, 50, told BBC Sport.
"Coming back was an even bigger problem. There were not enough signs to say where buses were leaving from and there weren't even any buses available - nor taxis.
"Thousands of us were looking for buses after the match, asking anyone and everyone where they were leaving from but we couldn't find them."
Mr Moodley eventually had to walk through central Johannesburg to pick up his car, with Wits the nearest of the four venues to Ellis Park.
For that reason, Wits was so overcrowded the parking closed some two hours before kick-off, forcing drivers who had already sat in the gridlock to head away from the stadium if they still wanted to use the system.
One disappointed fan told the BBC he would stay at home next time because it's "far easier to watch on television" than use the park-and-ride.
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