Margot, but that’s just one interpretation of acceptable behaviour.
People have all kinds of different interpretations of what is right/wrong to bring and how to respond to a host’s answer to the question ‘can I bring anything’.
One thread had someone saying that when anyone asks what they can bring, they always say ‘oh no need to bring anything’ but then expect the person to still bring a contribution to the meal. Another person said they say nothing is needed, just the pleasure of your company, but then feel upset if there aren’t decent wine and choices brought....saying that after they’ve hosted and paid for a meal, they’d expect that.
So lots of people think the answer to ‘what can I bring’ is meaningless and they should be contributing. Some will see that as a contribution to a meal such as BBQ which can often be more of a ‘bring and share’ type thing than a formal meal, and others will think they should bring a gift or both a contribution and a gift.
There is no official ‘if you don’t bring a contribution you bring a gift’ although lots of people will.
The good host receives every guest warmly and is appreciative of anything they bring and never comments on those who arrive without anything. They also then don’t spend their time afterwards dissecting what people brought, how much it cost or whether it was what the host asked for or likes.
You invite people for their company. If you need explicit things for a bring and share type meal, then make it blindingly obvious you’d like those specific things brought. Otherwise, accept guests might bring some things or nothing and rely on none of it and don’t judge them for it. If you’re in it for the gifts or food from other people, hosting probably doesn’t suit you. If you get offended or consider it rude if someone brings things they weren’t asked for, or bears a grudge over things not being brought, or has an extremely rigid sense of what is and isn’t the done thing, just don’t host.
Too many people have far too rigid views of ‘right’ behaviour and forget that not everyone has heard of the ‘rules’ they are living by.
Don’t forget, sharing food, even when you’ve been told it’s not needed, is also very cultural for lots of people. They love to ‘bless’ people with a homemade food item and a way if showing they value them.
Honestly, loads of threads moaning about those who turn up without anything....but then moaning about people bringing things. You just can’t win can you. Lighten up people and consider what hospitality and being a good host is all about. Mean thoughts and bearing a grudge and judging someone to be ‘rude’ for an item they brought....hardly the marks of a generous or good host!