You know this, you're just playing with people whom you think are dumb. This is just trolling.
I know that gays as individuals were not excluded, but such groups were not allowed. The primary difference is that the St. Patrick’s Day Parade has a religious aspect while a gay pride parade is a purely political event.
The religious exercise should be protected from instigators, while a political event on a public street should not exclude citizens from voicing an opinion.