I coach youth soccer and t-ball, and one of the first things I tell parents is that such behavior will not be tolerated. I will remove them from practice or a game if they behave in an inappropriate manner.
If I don't put up with it from parents, imagine my patience for coaches who do it.
“Activism is a way for useless people to feel important, even if the consequences of their activism are counterproductive for those they claim to be helping and damaging to the fabric of society as a whole.” - Dr Thomas Sowell