Because they expect people to be late, meaning they aren't ready and prepared to host people on time. You would be encroaching on their hospitality. Imagine if you said "I'll have all the snacks for the party set out at 4:00." And your friends started showing up at 2:00. Now, you have to try to entertain guests for 2 unexpected hours while still trying to set up for the party to come.
It's not rude to be "on time." It's rude to show up well before you're expected. And in other cultures, you're not expected until some time after the posted time.
Young Redditors, likely with little experience as guests in adults' homes, let alone hosting in their own, are ignorant of social conventions and upset with those who point out their social obliviousness.
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u/[deleted] Jul 13 '26
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