Sometimes their team wins, and sometimes it loses. Sometimes they cheer. Sometimes they curse, scream, even cry.

But there’s something the New York sports fans almost never experience:

Being characterized as restrained and sane in comparison to their counterparts.

Yet that’s the scenario during this latest World Series, with the New York Yankees facing a ballclub from the one sports city with a fan base that has earned a reputation for even more rambunctious and obnoxious behavior. Passionate? Crazy? Cruel? Philadelphia sports fans have been called plenty of names, but none any more demeaning than those they’ve called opponents, their own players and even a jolly gift-bearing icon over the years.

You’ve probably heard some of the stories. At the since-imploded Veterans Stadium, where the football Eagles and baseball Phillies played for more than three decades until 2003, no one was spared. Not the Easter Bunny … booed. Not poor Santa Claus ... famously pelted with snowballs back in 1968. Not opposing head coaches such as Jimmy Johnson, or perceived traitors like outfielder J.D. Drew, both of whom found themselves dodging barrages of batteries. Not future Hall of Famers such as Cowboys receiver Michael Irvin, who did receive cheers in 1999 … for laying motionless on the turf with what proved to be a career-ending neck injury.

The next day’s headline in the Philadelphia Daily News?

“Unspeakable, even for us.”

That was saying something, considering that two years earlier, Veterans Stadium had opened a jail (with a court and judge) to take quick action against the most belligerent Broad Street bullies. Even in the Bronx, that’s never been necessary.

And if you think Philadelphians treat their enemies harshly, look at the way they’ve treated some of their own, from Ron Jaworski to Donovan McNabb to Mike Schmidt to Jimmy Rollins, and even at times Charles Barkley. (Allen Iverson seemed to get a pass, at least from most of the population).

Even All-Stars came to accept the reality: if you don’t perform perfectly, you will hear about it. Loudly. Jaworski led the Eagles to a Super Bowl appearance, but it wasn’t enough. Schmidt hit more home runs than any third baseman in history, but he arguably got more grief at home than any superstar in history. McNabb was booed on draft night, when Eagles fans wanted Ricky Williams. While his numbers might someday get him into the Hall of Fame, he still can’t seem to earn a place in many Philadelphians’ hearts.

And last year, while appearing on the Best Damn Sports Show Period, Rollins said this about Phillies fans: “I might catch some flak for saying this but, you know, they’re frontrunners. When you’re doing good, they’re on your side. When you’re doing bad, they’re completely against you.”

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But who are they? Just like sports fans in so many cities and towns, some of them are doctors, lawyers, accountants, business leaders — people who act proper and professional when outside the stadium. Then they get inside a stadium, or get on a talk show or a message board, and they become hypercritical and hysterical, obsessed with the outcome of a game that they’re not playing, and enraged by anything that doesn’t go quite the way they demand.

And it’s not just the fans in Philadelphia, or even New York, who act this way. You’ll find this behavior in any sports stadium or arena in America.

“It’s without a doubt one of the great diversions that you can have in entertainment,” said Dr. Richard Lustberg, who runs the psychologyofsports.com site. “People take that entertainment and then relate it to their own lives. People can understand getting to the precipice of getting to a promotion, and then succeeding at it or not. The merging that occurs between fans and players is the involvement that takes you away from other issues in your life, but also the understanding that you too have been involved with highs, lows, ups, downs in your life, and that’s how you relate.”

And sometimes, you go a little nuts.

Why do sports change the way that otherwise calm, rational people behave?

Christian End, an assistant psychology professor at Xavier University specializing in sports fan behavior, said it stems from a natural tendency to conform to the standards in a particular environment. In the average workplace, it might not be typical to yell at other people. But in the stadium, it is. And in a stadium where fans are known to be confrontational, and where alcohol is readily available, acting out becomes even more acceptable and expected. By day, you’re a CEO or attorney, careful not to offend because that would reflect badly on yourself and your business. By night, you’re just another guy who expects Rollins to come through in the clutch, and won’t be shy about screaming so, in the most creative and colorful language.

“When we go to a situation where our group identity becomes more prevalent in the forefront of our mind, we are more likely to leave behind some of the standards of our personal identity,” End said. “There’s been a general acceptance that you can go to the ballpark and act in ways that you normally wouldn’t. Anything goes.”

And that offers an outlet that, in Dr. Lustberg’s view, can be healthy.

“In that environment, it’s a great place to hang out your issues,” said Lustberg, a Long Island resident. “It’s a lot easier to come home after screaming at a Yankee game and be hoarse on Monday morning, then to come home screaming at your wife and children. At a sports event, screaming is acceptable. If you are screaming at people on 42nd Street, that’s not so acceptable. And if you are a highly critical person, it’s a lot better to be questioning Joe Girardi’s moves than to go in and tell your boss that he sucks. Joe Girardi is a lot better target.”

Peer pressure often plays a part in the chanting, taunting and cursing.

“It’s natural in that situation to seek social approval,” End said. “One person in a section yells something, and you think, ‘If they think that’s funny, just wait until I yell this.’”

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Some Philadelphia fans seem to revel in the reputation that precedes them: that they make it tough on opponents, and that they have high expectations for their own players.

“Groups strive to make themselves distinct from other groups,” End said. “They also want to be better than the other groups when you compare them head-to-head. If they begin to believe that the taunting is having an impact on the game, they sort of take pride in being the best at providing a distraction. That can help them buffer, and make them feel better if the team isn’t as successful head-to-head.”

So what about this head-to-head matchup of fans? Certainly, Yankee fans aren’t shrinking violets; they’ve done their share of shrieking too. And they’ve been slapped with a different sort of stereotype: arrogance and entitlement, a product of rooting for a team with the most championships in American professional sports and the highest payroll as well.

“It’s good versus evil,” said Joe Queenan, a humorist and author who was raised in Philadelphia but is now a New York resident. “You are talking about a city that is passionate about its sports, whether the teams win or lose, against the Yankees. Some teams win games, and some teams buy them.”

In his book "True Believers: The Tragic Inner Life of Sports Fans," Queenan wrote: “The Phillies and Eagles are exactly like nicotine, a preposterously noxious semi-hallucinogenic substance capable of giving great pleasure for brief periods of time, but that will ultimately destroy your health.”

Queenan quarrels with some of the perceptions of the modern-day Philadelphia fan. He spots “a huge difference between young Philadelphia fans and older Philadelphia fans.” Older fans had good reason to be fatalistic and ornery, after watching great collapses (the 1964 Phillies) and team after team come close but fail to win a championship.

“One of the interesting things about sports is it’s not passed down from generation to generation,” Queenan said. “The kids don’t care about the 1964 Phillies. They don’t care about the years when the team stunk. That’s all ancient history to them.”