Fewer fans singing "Take me out to the ball game"

FILE--MIAMI, FL - APRIL 13:  A family sits in an empty section of seats during the Miami Marlins and Philadelphia Phillies game at Marlins Park on Apr...
A family sits in an empty section of seats during the Miami Marlins and Philadelphia Phillies game at Marlins Park on April 13, 2013 in Miami, Florida. Major league U.S. sports are suffering a decline in ticket sales. Jason Arnold

Major League Baseball's All-Star game on Tuesday night was set to draw a full house -- some 45,000 people filling all the seats of Citi Field, home of the New York Mets.

But the game appears to be an exception rather than the rule this year when it comes to putting fans in baseball stands. MLB's total game attendance is down by 417,192 people so far compared with last year at this time, according to Baseball

In fact, live attendance in other U.S. sports—pro basketball and football, motor sports and even college football—has declined or leveled off the last three to five years.

"The drop-off in attendance for live sporting events is getting worse," said Lee Igel, a professor of sports management at New York University.

"You've got a lot of competing factors in this, even bad weather," Igel explained. "But with the economy still sorting itself out, there's the huge cost of going to live events plus fighting through traffic and parking just to get to the games."

"And even more important is the experience of watching games in the comfort of your home on a big screen without the hassle at a stadium," Igel said. "That keeps a lot of people away."

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The fall off in baseball attendence has gotten so bad, that the Miami Marlins—the team with the lowest attendance figure this year as well as the worst win-loss record—decided to close the upper bowl of their stadium for some home games.

Even baseball royalty, the New York Yankees, have seen a decline this year of nearly 2,500 fans per game and are selling half-off tickets through the online coupon service Groupon. Their bitter rivals, the Boston Red Sox saw their record 820-game sellout streak come to an end this summer.

This past season, several National Basketball Association teams, like the Sacramento Kings, the Detroit Pistons and the Milwaukee Bucks, had major attendance drops. The Pistons averaged only 13,272 tickets sold per home game while playing in the 21,000-seat Palace arena.

To lure fans for a game against the Dallas Mavericks in December, the Phoenix Suns offered a money-back guarantee on tickets, promising that fans could get a refund if they weren't satisfied with the team's performance, or even if the beer in the arena was flat.

The attendance drops have spread like a fan wave. A NASCAR auto race in March—the FC 500 in Bristol, Tennessee—had a reported attendance figure of 80,000 people, but that left a half-empty speedway that normally fills up with 160,000 for the race.

For 30 of 35 college football bowl games this past season, the average announced attendance was 46,278—down 5 percent from 2011-12 and 8 percent from 2010-11 through those same games.

Attendance at NFL games this past year was up slightly according to the NFL, but that was after some 4 years of decline. The league reached an all-time high in 2007—18,137.224 total attendance— but in 2011, dropped to its lowest level,17,391,163, since the league expanded to 32 teams in 2002.

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Only pro hockey, with its rabid fan base returning after a lockout and shortened season this past year, saw an attendance increase for a third consecutive season.

"All the major sports except hockey have major challenges getting people to attend live events these days," said Mark Conrad, a professor of sports law at Fordham Univeristy.

"Most sports can't just depend on die-hard fans to fill up seats," Conrad said. "They've had to offer a lot more than just the game."

To entice fans—while forgoing money-back guarantees—stadiums have built mini theme parks for families while expanding traditional ballpark food like hot dogs, hamburgers and garlic fries to sushi, fresh sliced tuna and gluten-free and vegetarian offerings like gourmet salads.

"There are more firework nights, rock concerts and even religious nights in some parts of the country to bring people in," said Conrad.

"It's more like a trip to Disneyland than a ball game," said Lee Igle. "The questions is, is this enough to bring fans in? Some that might just want to sit back and enjoy a game might think it's overload."