A polar opposite of the Minnesota Long Goodbye, the [Insert Nation Name Here] Goodbye/Leave/Departure/Way has morphed from it's original ill-mannered connotation, into a mark of cultured sophistication. Leaving a party without saying goodbye was once something so gauche that only foreigners did it.
When it's time to leave a party, make a beeline for the door. Don't tell anyone; don't thank the host; just get out of there. What you call this rejection of a polite farewell, however, depends on where you live.Thu-Huong Ha | Quartz
Knowing the origin of the Irish Goodbye makes it funny to see actual Irish people clarify that this kind of behavior is not the done thing over there:
This kind of linguistic twister is yet another one of those examples of the fluidity of language like the word "decimate", which once defined a reduction by one tenth, but now means "to cause great destruction or harm to." On the propriety of leaving without saying goodbye, I'm torn on whether it's the right thing for me to do, but feel that it's totally correct for my guests to choose either or.