By “Blighty” are you referring to Great Britain, or a town in NSW, population 326? That seems to be a vast difference!
And I am at a loss to imagine security guards checking invitations at a church door and giving heave-ho to the unworthy. What particular denominations have you polled on this? How many different types of ceremonies have you crashed?
You are at a loss to imagine something that is extremely common worldwide. Though not "security guards". You don't need security guards, because when a little lady tells you to please come back in an hour and a half, people don't push her aside and scream "freedom!".
Especially with churches in most cases nobody will be shown the door especially as in (Christian) church tradition the wedding is before God and the community, which traditionally is the village. Nonetheless many cultures will see it as somewhat private. Especially the reception or a non-church ceremony.
I refer to my homeland as “The States” out of courtesy to those from Canada, UK, Australia, but I had to rack my brains, and Wikipedia, about “Blighty” because it seems archaic, stilted, and arcane in a tech forum.
I’ve heard England called a lot of things by its citizens, but I was under the impression that “Ol’ Blighty” died out with Queen Victoria.
At least online, yes.
In all my years on the Internet and written forums, as well as watching British TV for 50 years, there has been no notable usage of “Blighty” that caught my attention.
If I had been aware of the usage, (other than archaic slang) I would’ve learned it sooner. But it’s notable that this Anglophile hadn’t been bothered until the Year of Our Lord and Reign of His Majesty Charles III, 2025.