DD is 23 and is briefly living at home between gap year and moving in with her boyfriend in January.
On Sunday DH and I had some guests over, they arrived at 11, left at about 8pm, didn’t have dinner but did have lunch (we ordered it in). DD knows the guests well, would class them as family friends.
DD and her boyfriend didn’t come down stairs until about 3 o’clock, then they sat with us all, drank some wine small talked etc, before going back up to her around about 5:30. At 7pm her boyfriend came back down to collect their food delivery from the door, they hadn’t checked with anyone if they wanted anything ordered.
YANBU - They were rude, they should have come down and said hi much earlier and had lunch with everyone, or they should have checked if anyone else wanted food ordered.
YABU - They didn’t do anything wrong, it wasn’t their guests, so not their job to accommodate them.