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Yes. It's pretty much the worst city in America.

In front of her children, Willow and Piper, former Vice Presidential candidate candidate Sarah Palin was booed, as she was introduced to drop the first puck at the Philadelphia Flyers' home opener.
Eagles' fans, including future governor Ed Rendell, pelted Dallas Cowboys' players and coach Jimmy Johnson from their arrival until game-time with snowballs.
Eagles' and Phillies' fans are both known to violently attack visitors in the stands and parking lots who dare to display their own teams' gear. Rather than hang their heads in shame over this despicable behavior, Filthydelphia "sportsmen" actually brag about it.
They've physically attacked a visiting hockey player as he sat in the penalty box.
They threatened and rocked the car of then Eagles' head coach Dick Vermeil's wife and daughter as they tried to leave a game.
They threw D-batteries at a center fielder who refused to resign with the Phillies when he returned as an outfielder for the Cards.
Criminal acts at Veterans' Stadium were were so common that the city installed a court, magistrate and a jail inside the stadium.
On Oct. 11, 1999, Dallas Cowboys receiver Michael Irvin suffered a career-ending neck injury at Veterans' Stadium. While Irvin lay motionless on the ground, Eagles fan cheered. As medical staff treated and restrained Irvin for transport off the field, the cheers and catcalls grew louder and until louder as Irvin was driven off the field.
In addition to Santa Claus, Philly fans have booed children performing dance routines, children throwing ceremonial pitches, and a half-time sky diver who broke his legs landing awkwardly on the field.
In response to violence, vandalism, and a number of deliberate vomiting episodes where Eagles' fans threw-up on visitors, young children, and even police officers, the city banned all beer sales during games and all tailgating for the 1989-1990 season.

I recall ex-Phillie Jayson Werth broke his wrist in 2012 sliding for a catch in the outfield as a National, they cheered.

Freegards

There is a bit of mythology here and other cities have bad fans as well.

They claim they did not boo Santa Claus, that his sleigh had an advertisement on it and they were booing the commercialization of Santa.

They also threw snow balls at him.

As a former Chicagoan, I can tell you that our impression of Philadelphia came from their sports teams and their fans - the teams consisted mostly of thugs and dirty players and their fans made the behavior of Chicago team fans look like that of opera patrons. And their fans actually HATE their teams when they lose, and hate them somewhat less when they win.