Your host is a foodie
Foodies often like the company of other foodies. If you are part of this tribe, it will not be news to you to say that any self-respecting foodie, whatever the occasion, will always appear with a mysterious bottle, of which only he or she knowns the origin, how it was made, the perfect food to drink it with, the state of its global stocks and even the best way to find it. If you are not a foodie, this information can come in handy. You do not, however, have to play by these connoisseurs' rules which can sometimes be a bit over the top. Just come as you are, with what you like. With a bit of luck, your hosts will not know the bottle you have brought and think you are one of theirs.