The champs pleased the crowd while showing off the city's first Lombardi Trophy ... with Jason Kelce's mummer outfit -- AND expletive-filled speech -- stealing the show.

But the fans also provided plenty of entertainment as well ... bros were crushing porta potties just to get a better look at the action.

And, of course, there was a bit of violence ... but that shouldn't come as a surprise.

Fun fact: Bud Light teamed up with Eagles lineman Lane Johnson to hook fans up with free beer. But who knows if that even had anything to do with the debauchery -- Philly fans be wildin'.

#FlyEaglesFly