I believe that on the first night I went to Gatsby’s house I was one of the few guests who had actually been invited. People were not invited – they went there.
– F. Scott Fitzgerald
The Great Gatsby, Chapter 3. Nick Carraway is invited by Gatsby to his party by a handwritten note. Everyone else shows up without an invite. Nick speculates that if they just show up they will seem high class because they are socializing with the West Egg elite