[old and tired]

If a parishioner wouldn't be excommunicated for having a homosexual relationship why would they excommunicated for just marching in parade supporting homosexuals?

Because homosexual activity is sinful. We're all sinners so no particular sin is going to get you thrown out of a Catholic Church. But marching in a gay pride parade is an *endorsement*/denial of sinful activity in direct violation of the Catholic Catechism and that is a reason to excommunicate.

[Atlas Sneezed]

I would call it “scandal” by the traditional definition.

[count-your-change]

I think I’d take Paul’s words as informative, “...Remove the wicked man from among yourselves”. (1 Cor. 5:13).