I guess the question is, do you feel safe and do you feel others are safe. If at any point that is no. Report it and explain accurately why you felt yourself or others were unsafe.
You are most likely refereeing a games where the players, coaching staff and anyone else associated with the clubs invest a lot of time, effort and money throughout the year.
As long as the celebrations do not spill on to the match during a game or are dangerous. I am sure the people who are partying have a reason to, and this is not a bad thing.
Take a step back and enjoy it!